Instead of making a traditional step-by-step walkthrough, I decided to with a simpler version: Telling the hard parts
Look around in the metal room, what do you see? A switch? Pressing it does nothing useful, instead search for an X mark and break that wall. Inside there is a button
If you are playing with someone else, you are bound to save him, or kill him. They keypad works that you have 3 guesses, guess them wrong and he dies and another door opens. If you are playing solo noclip through the fence, yes this is a permissional noclip part. For the actualy code to be found, the code is written above the button that is used to open the first door.
If you were paying attention, the spike room had a writing that pointed an arrow to the right button. If not, the right arrow is the correct one, left one kills you
Here, its all about speed. Press the button and wait for the vents to break, immidietly jump into one and avoid getting crushed by the spikes.
Simple: 1 must enter the room and press the button to kill himself. But theres a catch: Everyone else but the person(s) in the small room will die.
To open the big metal door, the players must flick 3 switches. When each one is switched on you can use the button to open the door.
To find the safe, players must enter the bathroom that has only 1 toilet. Look to the left and you should see a weird tiled surface, break it.
To open the safe, a code must be inserted. The code can be found from the wall of the room with the soft walls and electric chair. In the jail, you know? Next to the door that takes you outside.
Answer is easy: You just go through and try to find out, only 1 person gets to the happy place. Other get a text: "You have been left to rot".