First Person Character Falls Through Floor

I imported the first person controller and placed it in the scene, but for some reason he falls down through the floor. I put the character high above the ground. My floor has a rocky cliff texture.

You may have placed him too low and he is inside the floor.
Or you haven’t made the floor out of a terrain.

ur terrain must have a collider. if u set it to a trigger it won’t work

1.Make sure you have a collider applied to the floor.
2.Make sure the FPS controller is not intersecting with floor, it should be above floor.
3.Make sure you have a collider applied to FPS controller.