Crouching?

[Saw3]

Hello, I am a new player to the game and I think it is awesome, just now at the begining u are at some place where the door is stuck and u need to find another way, and as you probably kno is that u move some boxes and a little way is opened to the next room, tho you cant just walk through it you need to crouch some way and it doesn't say in the tips that come through out the game, tho I am playing the Demo, it is included to be abel to go further then that i hope?