My camera isn't following the code

Hello. I’ve been following this tutorial and for some reason i cant get the camera to move like he’s does. I’m completely new, idk what to do!
pls help

this is the tutorial:

Please post your camera code. Without at least this information there is no way anyone can help. In the post editor there is a </> button which will let you paste in pre-formatted code. It would also help if you described the intended behavior and the observed behavior.