How do I make a block camera that makes the player facing it?

So I tried earlier making a script that make the camera not be able to move but it didn't work. So I asked my friend and he said that all I have to do is put the main camera in the part but it didn't work. So I am asking if I was doing something wrong or do I need to insert a script.

I am relatively new to coding so there might be a few questions on the answer.

Please reply

Thanks