After being captured by the combine near the start of the game I have gotten out of the car crash and I am stuck at a wall that I don’t know how to get over?
You need to use the teleport style controls to jump in most cases. You won’t be able to perform the motion naturally. It would be quite risky to have to do that jump in real life while wearing a headset. Turn around and go up to the ramp kind of thing behind you. The game will prompt you to use the jump mechanic from here.