Metal Gear Solid 2

Tanker: Firefight below deck

Deck-2, port

There is an announcement that all soldiers shall gather and it addresses the enemy, but you should now be careful as there can be more soldiers in one spot, but that is a bit ahead.

So follow the long hallway. You pass by some intendations. The first of these has a RATION in it, the second one holds USP AMMUNITION, before reaching the 3rd one wait a bit as a sentinel is coming your way now. After you got rid of this guy follow the hallway to the end. Watch out, another soldier comes around the corner, but he is distracted already...
Knock him out, get the USP AMMUNITION and follow the crossing hallway around the corner.
At the end of the crossing hallway another soldier is waiting for his well earned headshot. He is sleeping almost all the time anyways, but be careful even though, you never know if they just pretend.

After this soldier you step through another door as there is nothing else to do here.

Deck-2, starbord

The Shootout

After a short and boring passage through the hallway you get engaged in a shootout. Here are some hints:

Take cover behind the box.
Watch out for the handgrenades the soldiers throw at you and change position if one is coming in.
User handgrenades yourself.
Aim really good!
Watch your healthbar and eat a ration if needed.
In the hallway behind you is more ammunition and a ration.

When you take these hints into consideration you will get past this shootout with some tries, keep a cool and strong hand and hope for some luck.