The solution is based on the US version of the game for Xbox 360, so there may be differences for the Spanish version and / or for other platforms.
The game starts in Cuba and after the introductory scene you gain control of the character by holding an M16. Wait for the door to open and go out onto the street, where you take out the two enemies that come out of the police cars following the accident. At the roadblock, turn left and advance to then enter a car: all you can do is press the button to accelerate until the screen goes blank and another cutscene interrupts the action.
Return to character control while in a forest and sliding down a cliff. In the building you enter you are ordered to silently eliminate the guards: to do this, press the melee button while you are behind an enemy and he will be strangled by your character. Then go out the main door and wait for the Cuban army to pass, then queue up to Woods (on which the word FOLLOW flashes) until you see a man running up the stairs: kill him and do the same with his companion who comes out of the tall and the two that emerge in front of you. Then go up the stairs and kill the soldiers inside, then the ones on the path to the right, but not before having collected the Intel behind the rocket launcher. Continue towards the gate, go up the stairs and enter another house. Carefully walk down the L-shaped corridor, where enemies hide behind makeshift barriers. The next sequence, in which you kill the three men inside the room at the end of the corridor, takes place in slow motion. Pick up the RPK Gun from the table if you like and go up to the second floor. Fidel Castro shields himself with a woman: aim at his head and kill him. You will also be forced to kill the woman who tries to attack you. Exit to the left and follow Woods to the porch, killing the three enemies. When you see Bowman throwing a man off the balcony, enter the room he came out of and pick up the Intel from the table on the left. Make your way up to the lower level and from there go out into the courtyard where you can pick up the rocket launcher. A skirmish with enemies takes place outdoors. If you want, you can stay covered and leave the dirty work to your comrades while waiting for Carlos to arrive. Then cross the sugar field to the wall, drop down the mountain and reach the hangar, inside which, climbing the ladder on the left, you come to an Intel. Reach the indicated point by fighting through the airport. Get your hands on the automatic machine gun and don't worry about bullets as you slaughter the enemies on the right. Since the road is blocked you will have to get on the anti craft gun and clear the passage for the plane to take off. In short, you are stunned and a cutscene concludes the first chapter.
After an introductory video, you find yourself in Russia, while a guard is beating you up. It is actually a diversion and you quickly strangle the guard from behind. Armed with a knife, follow Reznov through the tunnel, stabbing the guard who jumps on you if necessary. Made the acquaintance of Sergie go up using the elevator. At the end of the fight you can finally get your hands on a gun. The next section can be tackled simply by following your two companions and carefully listening to their indications about the side where it is best to take cover. After passing a couple of gates behind Reznov you come out into a snowy courtyard. You must therefore enter the building and go up the stairs. Before moving forward, pick up the Intel from the table on the left, then continue up the hill. Upstairs, use the slingshot to take down the three enemies (using just three shots, you also unlock a trophy / objective). Now go back downstairs and pick up the shotgun. Grab it, go out through the new door and blow the lock to continue. Kill the two guards along the road on the right, then two more and finally the ones guarding the courtyard. When the situation is calm, enter the building and go up to the second floor to land the helicopter by hitting it with that sort of harpoon. Exit this structure through the back door on the lower level and make your way to the building that stands out in front of you. Inside, get rid of the couple of enemies, then grab the Ak 47 rifle, equipped with a grenade launcher with which to get rid of the enemies hidden behind the walls. The grenades also come in handy against the two shield-protected enemies that you must face shortly. Go upstairs and make a clean sweep. When the enemies try to lock you inside the building Sergei will take charge of locking the door so that you can slip and exit. Follow the marker and flip the switch, then take the dark corridor to the right and pick up the Intel from the table to the left. Climb up behind Reznov and kill the two enemies that parry in front of each other, after which continue along the walkway that leads to a room in which nothing happens for about a minute: do not get distracted as soon an enemy breaks in and it will take a good part of your paraphernalia to take him down. You will encounter this big enemy again in the next section where you escort Reznov to the room where you can pick up the minigun. If you can, keep some grenades for this juncture which turns out to be quite challenging. Use the minigun to blow up the arriving truck as soon as you turn the left corner of the building. Then advance towards the indication killing everything that moves. There you are stunned by gas and a cutscene interrupts the action. When shooting, immediately pick up the Intel from behind Reznov's motorcycle, then get on the other bike and exit through the window - drive through the checkpoints, firing when needed.
The mission is simply a long, non-interactive sequence.
Follow Woods to the end of the tunnel, then look at the panorama with binoculars as your fellow soldier passes you until you see Weaver's execution. Keep following Woods while protecting yourself thanks to the pipes and silently kill the two guards as suggested by the game. After a cutscene, follow Woods further to the meeting with Bowman and then further on to the missile silo area. After Bowman kills two guards enter the entrance hall of the building and get rid of the three men in the room you enter. Go up to the second floor where five guards await you. He also killed these you can go upstairs, patrolled by four guards. Move to the ladder and pick up the Intel near the computer, then climb up and throw the waiting enemy downstairs. After getting rid of the other two remaining enemies, watch Woods who, after going upstairs, hands you a crossbow with which you have to protect your companions by killing all the enemies that arrive. In short you will be told that you will have to throw a taut cable through the window: do this and your character will slide along the cable, all while the game goes into slow motion, leaving you the task of shooting everything that moves. using an MP5.
When the game resumes, follow Woods and Bowman again, keeping an eye on the timer. Go over the rail and continue up to the ladder, shooting at the hidden enemies (against which the crossbow is always useful). When you reach another staircase that goes down eliminate the enemy behind the barrel and continue, turn left and reach another staircase, being careful of the dangers coming from the left. When a wall blocks your path, blow it up with the C4, accessing a control room, on the bottom of which is an Intel. After you are notified that Plan B is in effect, follow the marker that leads you to a prototype rocket. After shooting him, follow Weaver down the tunnel, where by collecting the shotgun you can make your way with ease. Turn right, getting help from your teammates' fire if you are in trouble, and cautiously advance towards the control room, densely populated with enemies, particularly on the right side. When you have managed to clear the room of the enemies, walk along the corridor. Stop at the bottom, where you see a room with a projector and look for the Intel near the terminal. After the checkpoint at the end of the corridor, take another corridor that turns left. Kill all the enemies, paying attention to those that emerge in the smoke, to close the chapter.
Upon exiting the tent you are greeted by Woods who explains the details of the mission as you are transported in a jeep. In short, you end up in the trenches to escape from the bombs: make your way to the area in the open field where you are attacked by an enemy: to free yourself you have to press the button indicated on the screen. Proceed to the fork and turn left, sneak under the tank that fell into the trench and continue crouching until you reach the detonator and press it. Continue to the next one and activate that too, then enter the hut and use the turret to slaughter the enemies. Before continuing, go up the hill and reach the long tent to find an Intel in the middle of some boxes. Go to the next cabin and grab the rocket launchers to take down the three tanks, then follow Woods back down into the trench and pick up the Chine Lake Launcher. Back in the open, kill a couple of enemies on the right while waiting for Woods' next move. After the napalm rain go down the ladder that leads into the bunker and kill the guy inside, and possibly the other two present (their absence depends on the possibility that you have previously killed them outside). Stocked up on ammunition, continue eliminating the turrets, starting with the one behind Woods' hideout. The next is in the tunnel on the left. Before you get there you may want to collect the Intel in the small bunker on the hill. Then watch Woods kick a barrel and do the same with the second and third, further to the right. After the checkpoint, go through the exploded trench and reach the scorched forest where a fight takes place. It is probably easier to go up on the right side; however your goal is to get to the top of the hill.
When the game resumes, shoot the guy who is about to execute Woods, then continue following your partner into the trench, turn right and watch out for the American flag that signals the position of another Intel, resting on a makeshift shelf. Soon you get into a jeep and from there you will have to take down some tanks. The former is not much of a problem, you will probably just need to shoot straight in front of you. After a curve to the right you will have to deal with two wagons. A little further on you will find one in front of you, another less visible on the left rather distant and finally the last one still further left. Using just six missiles you will unlock a trophy / achievement.
After the spectacular introductory sequence, grab the Spas shotgun from Woods and exit into the corridor. Use the weapon on the three dudes who run towards you, then go all the way down the burning corridor and watch the helicopter shoot some enemies. Kill the enemies along the corridor to the room where a civilian is about to be killed. Save him by shooting the enemy. Climb up and shoot the enemies that are killing civilians through the windows, then turn the corner and take out the two looking out the window, but watch out for the soldier coming out of the stairs. Beyond, three more enemies await you, then two more hidden behind a wall. Go down the stairs and kill the two enemies visible through the damaged wall, then break down the door and kill the guy in the chair, then wait for his teammate to arrive. In the next room two enemies run towards you and a third comes out around the corner. The back room, reachable if you don't fall from the balcony, is full of weapons. From there shoot the guys below and wait for Woods to scream to enter the next room. Down the hall, break down another door and you will soon be rescued by Reznov. Cross the room and take the corridor, collect the Intel from the small room on the right, then continue to the end where you come out in a courtyard. Move to the battle area and arrive at the ruined building where, climbing up, you get the radio from a soldier. Then point the target to the air support and free the building from the enemies, then go down the streets and make your way up to the two exploded cars. Along the way, after a right turn, you find an Intel inside a house. Basically you can simply advance along the established path and call air support to clear the way of the enemies until Woods breaks down the gate allowing you to proceed. Help Woods knock down the next hostel before he passes out.
Upon awakening exit the building and enter the adjacent one, kill the two men upstairs, get rid of the guy on the balcony and jump through the window. After another interlude you will have to make your way through the burning building to a wall that has a large hole: be careful and kill the enemies on the right. When calm returns, cross the courtyard leading to the nearby building, enter and blow up the ceiling using the C4. Keep going until you see a tank explode through the building to the next where there is an Intel. then proceed further, to the next two floors. Immediately reach the upper one where you meet Woods. Kill the first wave of enemies, then wait for the second one, coming from the southeast, supported by a tank. Use the air support to eliminate the tank, then reach the boat that proceeds to your extraction within the twenty seconds available, closing the chapter.
Follow the on-screen instructions to complete the interrogation until you become an object of attention from the enemies. Collect the Intel in the corner right away, then kill the enemies and collect their weapons. Follow Clark up the trap door, then around the corner where a soldier ambushes you. Kill the other three soldiers, and continue to the enemy outside the window at the end of the corridor. Climb to the roof and watch the plane, then after Clark's scream take care of the enemies that come up from the right. Regardless of everything else, run and jump until a slow motion sequence starts, after which you can choose a weapon from Clark's supply. Exit and come out on the road, arrange the two that emerge from one side and the other, then continue and after a hairpin bend take care of the enemies on a balcony. Then exit to the left, as suggested, and save the woman by shooting the enemies chasing her. At the window, climb up to reach the other side and make your way clearing the enemies along the path on the roof, until the allied soldiers arrive. Go down to the room below which overlooks a small street: kill the enemies on the balcony at the end of the street. When you reach the bottom, slide on the pipe and take care of the two soldiers. During the next descent the action goes in slow motion and in that juncture you will have to eliminate four enemies. After the explosion, stock up on weapons and pick up the Intel from the left corner of the area where you come to the end of the drop.
Keep following Clark taking care of the enemies that jump out from the left until you can hide behind the statue. If there are other enemies left in circulation, you can deal with them from that position. Go to the area where Clark is hiding and kill the three enemies above you, preferably starting with the one armed with rocket launchers. After that go down again and enter the house where two enemies ambush you by breaking down the door. Continue along the corridor where two more enemies emerge on the right and others attack you from the back. Kill the enemies in the room on the right and make your way through the balconies. After killing the enemy behind the gate, turn right, shoot the two enemies (one of which is holding a rocket launcher, be careful) and reach the indicated point. Your job is to defend this area while Clark takes care of opening the passage. As soon as you can proceed, jump to the end of the corridor to view a cutscene. When the game resumes, kill the two enemies below you and go down to where they were. Continue the descent killing the enemies below. Collect the Intel behind you before jumping to the last platform. At the end of the cut-scene, collect the handgun and kill all the enemies that run towards you, then get on the van that came to your rescue.
Game video: gameplay
Follow Dimitri before collapsing unconscious. When you wake up, go up the hill and take out the enemies on the left. Carefully advance towards the house, kill the soldiers inside, then make your way to the garages. Some enemies emerge from the shed in front of you: take them out and then move in that direction. Inside, make your way to the indicated point, go through the hangar and finally reach the nearby building. Watch out for the enemy positioned at the window behind the blanket of snow. Then kill the enemies that come out of the building and the two half-hidden ones before reaching the interior. Go up and get rid of the two soldiers, then have the two do the same in the next room. Collect the Intel from the desk on the right and go down, exit the building and head to the right where you check out the mortar attacks. Then quickly reach the building on the left, take out the enemy on the roof and the one on the right, armed with rocket launchers, visible from the bottom of the burning building. Then focus on the enemy on the turret and on the one, not very visible, overlooking the window to his left. Launch a smoke bomb under the turret, then enter the building to the right of it. From there you can throw a smoke bomb into the group of enemies that blocks access to the hangar so that the mortar concentrates in that area. Enter the hangar and pick up the Intel near the black wall, then follow your team to the left. Don't waste too much time and get to the houses on the left as soon as possible because in this area the enemies spawn indefinitely. Launch a smoke bomb in front of the turret, then run under cover and from there take care of the enemy protecting the door below. Open it and take out the enemies on the left and under the table, then go up and reach Steiner.
When the game resumes, you find yourself in the midst of your fellow soldiers. Follow their footsteps through the old ship and once you get to the second floor watch the cut-scene. Back in control, an explosion frees you from the cell where you are locked up. Shoot the enemies in the room and those who come through the door. Move to the next room and make your way without forgetting the enemies on the balcony. Trigger the explosive then shoot the yellow pipe and escape down the ruined balcony. Make your way by shooting the two enemies in the door then keep running, stopping only to pick up the Intel before the last flight of stairs.
As the helicopter crashes, check the pilot's health only to witness his murder. So grab your gun and shoot the two in front of you. Then follow the on-screen instructions on buttons to press until you are on board a boat. Kill the four on the other boat then jump into the water and swim to the indicated spot, where you rejoin Woods. Take out the eight enemies that come down the path to your location, then follow Woods, as suggested by the large sign above his head. Continue to follow Woods while swimming, listen to Bowman's words, then place the C4 on the wall. Behind Woods, quietly sneak into the building through the window and melee the sleeping guard. Eliminate the patrolling guard in this way as well, then pick up the Intel behind you. Then drop into the water from the hole and apply more C4, then swim to the gate that opens and continue. Get to the ladder that leads you into another shed: go through it and exit, then use the detonator to blow up the charges. Now a fight begins: use the sniper rifle to place the soldiers furthest away on the bridge and those hidden behind obstacles, taking advantage of the armor-piercing ability of the bullets, then throw a grenade into the hut that is indicated to you. The hut behind this houses another Intel.
Cross the field and you will be attacked by a heavy machinegun. Take the path that goes to the right, towards the river where you will be prompted to take the rocket launcher and use it to take out the machinegun. After that take out the sniper rifle again and use it to stop the enemies coming from the huts on the left. After that, move in that direction, from which the enemies were coming, and take out the guy who maneuvers the turret. Shoot through the windows and don't forget the enemy between the two huts. When trees stop you from proceeding further, drop down the hole and follow Swift. Not long after, Reznov joins you. Turn off the flashlight, then stab the enemy who attacked Swift. Arrived at the end of the tunnel an enemy runs towards you shooting wildly. Kill him, then be ready to face two more soldiers in the room to the left. After moving objects blocking the path, enter another tunnel with Reznov, freeing yourself of the enemies. After the guy running to meet you, take the path to the left to collect a piece of Intel. Then around the corner to the right you find two guys waiting for your passage. When you have settled them, continue waiting to rejoin Reznov: keep your guard up because soon another enemy will try to attack you. After a few steps, foil another attack, then turn the corner and be ready to face three enemies. Continue by breaking down a couple of doors, then run when you start to hear the explosions behind you. Drop into the hole and run left through the tunnel that collapses as you pass. Soon you will be prompted to dig using the melee key. The arrival of Woods closes the chapter.
From the camp, head to the dock, picking up the Intel on the desk to the left on the way. Climb aboard the ship and after some time shoot at the trucks and houses using the machinegun or rockets, especially focus on the two trucks on the left and the huts on the hillside. Blocked by the dead end, retrace your steps, then pass the dam destroyed by helicopters and fire a rocket at the tower, then destroy the huts with the machinegun. After that, go to the truck on the right, as suggested by the game as soon as you have destroyed two more towers in the distance. Proceed by destroying other huts on the left, being careful of the troops advancing from that direction. When two boats appear in front of you don't waste time, but sink them with the machinegun, then dedicate yourself to destroying the tower on the right. After the left turn, other huts and other towers. From the dock you arrive at, a ship comes out and attacks you. Sink it too with the machinegun and rockets, but be careful as to be effective you will have to wait for it to get close, and at the same time you could be targeted by enemies on the hill armed with rocket launchers. After destroying the ship, your character passes out.
When the game resumes, move from the burning hut towards the river, arriving at the dock. After exiting the ship, pick up the Intel on the right, then advance until you see a flare launched into the sky. Get rid of the three enemies that attack you and find shelter behind a rock: from there look to the right to find the soldier hidden in the trees. Once the road is cleared, run into the jungle. There you have to deal with other enemies: the first target is the enemy sniper, as reported by Bowman. Then follow your team, killing the enemy running towards your position. At the half-destroyed barrier on the top of the hill, take advantage of the elevated position and kill all the attackers before descending and heading left, where a sniper is hiding in a tree on the right side of the path. Kill all the enemies that are hiding and, when your character claims to have killed the last one, proceed by climbing on the wing of the plane and descend to the right. Collect the Intel in front of you, then enter the plane. Collect the Dragunov (sniper rifle) and use it to reach the cockpit: you must keep the enemies on the ground at bay until the boat arrives. After killing the two enemies on the boats Woods signals the arrival of the helicopter, closing the chapter.
On the plane, alert your teammates to the presence of a truck, then direct the navigation system to the marker on the right and send your team to the shelter. Now move on to control a soldier in the field with whom you must eliminate the oncoming enemy platoon. Once this is done, resume directing operations: let the team exit from the back and have them kill the two hidden enemies before directing them towards the road.Then press the button indicated on the screen to make your soldiers hide when an enemy squadron passes, then direct them towards the barracks before regaining control of one of the soldiers in the field. Break down the door and get rid of the enemy inside the building, then turn your attention to the table on the left where there is a piece of Intel. Go down the stairs and blow up the computers with C4. Back in the role of the pilot, have the team move north twice.
When the game resumes, you are hidden in the snow. Let the enemy troops pass, then advance, but be ready to crouch again to avoid a soldier accompanied by a dog. Silently go around the house then drop down the slope following the instructions provided on the screen. Remember not to cover excessive distances with a single jump if you don't want to fall. Enter through the window in the building below and kill all the enemy soldiers, then look for the back door and from there go down the stairs. You are back outside in the snow: move carefully around the left turn and surprise one of the two guards, then let your team take out the other. As you advance, you are warned that a massive enemy deployment is in front of you. Advance slowly: After the garage activity has started, crossbow the patrolling man outside. Once this is done you have to kill, always with the crossbow, one of the men inside the garage: in this way your team will go into action, clearing the area. Go ahead and kill one of the two guys shoveling snow while your teammates take care of the second one. Go around the area and shoot the man on the roof of the base, then wait for the bulldozer to get close enough and shoot his driver. Now use a weapon that allows you to zoom in and deal with the enemy intent on setting up the guns inside the base. Proceed to the catwalk and take out the walking man, then blow up the door hinges to continue. After your partner has eliminated the enemy inside, take down the next door as well: focus on the guys on the first floor and leave everything else to your companions, then be ready for three enemies to break in on the other side. Move in the direction they came from and pick up the Intel on the left, then deal with the enemies downstairs. Destroy the satellite controls then follow the team onto the catwalk: following the rocket launch, jump to continue and join the group during the avalanche. Jump and hold the lever forward, then activate the parachute (as suggested on the video), then as soon as you land take care of the enemies in front of you. In short, you'll have to deal with a machinegun. Look for cover in the building on the right, inside which you will find three enemies. Move to the right, exit the door on the left and cross the open space to reach the building opposite. Before advancing to the projection room, grab the Intel from the table. After the cutscene you will have three minutes to escape: exit to the left and respond to enemy fire from behind the bins. When the team arrives, run to the door and kill the fleeing enemies, then reach the back of the truck and keep the enemies away by maneuvering the turret. While your teammates take care of the tampering, blow up the other trucks, but watch out for the rocket-wielding guy on the left in the meantime.
Kill the man who made you play Russian roulette and take his gun with which you kill the two guys in front of you. Then grab their Ak 47, then follow Woods and kill the two enemies on the right. When you are done you can look for supplies on the left. Advance along the path and deal with the two gunmen before approaching a room full of enemies. Kill a couple of them, then follow Woods again and wait for the moment to enter and finish the men inside. Pick up the Intel from the shelf on the right, then continue behind Woods to the left. Shoot the Russian, advance and quickly kill the enemies to be able to board the helicopter. Before landing, grab the Intel located on the table to the right. While flying along the way, shoot the boat, then shoot down the bridge using the missiles. Before you get to the village you will have to sink another boat. Destroy anything that moves, be it a boat, tank or helicopter. Move left and right to avoid the missiles that are fired at you, then return to take down bridges and pipelines. Then fly over a much larger village than the previous one. You are assigned four goals. Start from the right and move to the left: first the radar antenna, paying attention to the turrets around, then deal with the machineguns around the bridge before destroying the pipeline by following its path along the river. About halfway you will come across another concentration of machinegun. When you're done, head back to the first bridge to be attacked by a couple of enemy helicopters. After taking them down (keep your distance so that their machine guns are less effective) go to the indicated point to land the helicopter. Stock up on weapons and resume following Woods. Your companion immediately kills two enemies, and two others await you a few steps away. As you advance, you find three more soldiers hiding near a truck, including one armed with rocket launchers. Don't let your guard down because at the end of the fight other enemies emerge from the cave on the left. A little further on, a guy armed with a flamethrower awaits you. Free the prisoners and follow Reznov. After a right turn you come across a room full of enemy soldiers. Seek cover and take them out without haste, then follow the team's moves. Before you get to a dead end, explore the left corner of the room for an Intel. The ultimate danger awaits you at the top of the stairs where an enemy ambushes you. Then watch the movie that closes the chapter.
After receiving the signal open the chest and exit, go around the busy man at the table and hit him with the melee from behind. Pick up the Intel on the left in the corner and hide the corpse, then walk away following Reznov. Wait for the helicopter to pass, then follow Reznov's footsteps and melee down the man between the two houses. Collect his weapon and join Reznov in the hideout, go up the stairs at the right time and hit the man at the top. From the balcony you go up again to the roof, from where you see an explosion. Now be careful, as the enemies are all on alert. Go down to the lower level of the roof, go through it and from the pipeline to the next roof. Open the door and walk along the walkway, go down together with Reznov. After the door, kill the two soldiers arguing with the scientists, then expect an attack from two more soldiers near the elevator when you get out. Seek cover behind the wall and wait for another enemy to appear, sneaking across the room to the left. Defeat any resistance in the labs and pick up an Ak 47 with grenade launcher before proceeding further. Grenades come in handy right away in the command center to get rid of the guys on the second floor. Collect the Intel from the top of the monkey cages and follow Reznov, open the door and witness a cutscene. When the game resumes, you play as Hudson and you are inside a tank. Quickly take care of the two guys on the roof before they blow you up with the rocket launcher. Then clear out the cars on the road behind which soldiers are hiding. After the left turn blow up the road block, then turn right and fire two missiles to the left and right corners, then two more at the trucks in front of you. Get rid of the enemies left on the ground by the helicopter, then turn right and be very quick to locate and kill the enemies hidden there. Take care of the one on the right right away, then move on to the two on the left on the stairs, after which take care of the bushes and the jeep. Before the bridge, bomb the barriers mercilessly. After the helicopter has bombed the tank and poisoned the area with gas, move guided by the thermal viewer. After the reinforcements arrive, kill the enemies through the windows and approach the marker to see the building blow up. Enter the house on the right to collect the Intel from the shelves, then go through the destroyed house and go upstairs. Kill the three enemies waiting for you and go to the adjacent building, go down the stairs and observe the two helicopters: you need the Stella rocket launcher nearby to take them down. Continue and, when the gas has cleared, collect the Ak 47 with grenade launcher. Go down the slope and approach the buildings to spawn a group of enemies. Don't linger too long in this position as the enemies spawn repeatedly, rather use the first good moment to sneak to the left and hit the enemies beyond the windows from there. Approach the building in that direction and two dudes appear on the roof, while two others appear through the windows of the main building. After taking them out, take care of the others spawning outside the building. Take care of the enemies coming down the stairs immediately, then the ones in the back. When you reach the inside of the structure, proceed along the left corridor and reach the stairs.
Open the door and go left. After a few cutscenes, open the double door and go left and pick up the Intel from above the archive. Continue activating another cut-scene, go through the autopsy room and head right to collect a second intel from a trash can. Then go to the projection room, watch the movie and then go left. After another interruption, turn left again, into a room full of desks: on one of the first there is another Intel. Advance and a final cutscene closes the chapter.
As you gain control, move back and forth shooting at the targets, then protect the team from landing on the ship. After that, protect yourself from the helicopter attack, then make your way to the right where a bunch of enemies appear. Get rid of them and advance to be attacked by two helicopters. On the left, before the chest you can cross, pick up the Intel, then the Valerie rocket launcher nearby and defend yourself. Advance and dispose of the enemies in front of you, then respond to the fire of the others who come out the door. Don't miss the guy on the walkway to the left, after which head in that direction and enter the building, go down two flights of stairs and kill the guy in costume. Go down two more flights and reach the small control room: under a table on the right is an Intel. Go through the room and go to the pump room. Kill everyone to start a dialogue.
On resumption, respond to the attack that is brought to you almost immediately, then advance. Respond to the assault from the elevated walkway, then turn to the enemies exiting from the left and continue in that direction when you're done. Shoot the man who comes down the ladder and go up from there to the door at the top, controlled by two soldiers. Go through the door and watch out for the enemies hidden behind the crates to the left. Advance and wait for two more soldiers to leave the room, then after killing them enter the way they came from. After the explosion you find yourself swimming up to the marker, climb up the walkway and follow Hudson. Kill the two men, then turn left. Deal with the two enemies in the room opposite, then go inside and go up the stairs. Stock up on weapons, then go out into the hall and get rid of the two around the corner to the right. Continue down the corridor keeping to the left to avoid getting hit by the men inside in the rooms. After killing everyone in the control room, enter the adjacent room, full of computers, and respond to the onslaught of the two men who enter after you. Climb up and immediately kill the enemy behind the desk, then flash a flashbang to the opposite wall and crouch near the two stunned enemies. Collect the last intel from the desk in the small room and kill the last enemy on the floor. Now that the environment is clear, approach the terminal and activate it. After the explosion, follow the on-screen directions to suffocate the enemy. Abandon ship and swim following Hudson to finish the level.
Congratulations, you have finished Call of Duty: Black Ops.
Video of the solution - First level