How to make First person Collide with the ground

I’m very, very new to Unity. I have my terrain all fixed up, the Default First Person Controller. when I press the play button, I fall through the ground, Thanks:)

By “Default First Person Controller” do you mean the one that comes with Unity? That one should react to the world. Are you sure that the First Person Controller is not starting a tiny bit under the ground? Try moving the First Person Controller higher above the ground and it should not go through any more. If that does not work make sure both the First Person Controller and the terrain has a collider.

If anybody is searching this on Google, I had this exact problem and fixed it by setting the Terrain Collider on the Terrain I created with these settings:

     Terrain Collider
     Material    Wood
     Is Trigger    []
     Terrain Data  (NAME OF TERRAIN)
     Create Tree Colliders [✓]