What Collider is needed for this polygon object?

Question

Unity

This object in my project is used as a floor.

But I don't know which Collider will do!
If you want to clarify something, then write!

Answer 1

Usually Terrain is used for the ground (floor):
https://docs.unity3d.com/Manual/script-Terrain.html
https://docs.unity3d.com/ScriptReference/Terrain.html
And the corresponding collider for it:
https:/ /docs.unity3d.com/Manual/class-TerrainColli...