How would i make the character not move when you move your mouse?

So i really want to be able to look around in my game in first person without moving my character the problem is i can't find what to do that will change the game in this way iv'e been looking in the default scripts but i just can't find where to change this. If you know a method for doing this please reply. Well rip i don't really get how asking what methods to code myself isn't constructive.