Perhaps look up the difference between 2d and 3d to start.
Five Nights At Freddy's is a 2D game, but with 3D sprites, you can find all images in web, I have it, this is why the only real time movement in game is foxy running, and even it is a lot of images, I was working in a fangame with the images, but then I thinked "It will not be a new thing, a inovation" then I stopped
The point is: FNaF isn't a 3D game