How to make a 3D house walker?

Question

Unity

I have a house model created in sketchup. The house has walls, floor, ceiling, windows, doors (doorways), stairs and floors.
I export it to Unity3D.
How to create a mechanism for moving an avatar around the house? More precisely, how to take into account collisions and handle stairs (in the future, elevators and escalators)? Does everything need to be defined manually, or is there a ready-made mechanism for automatically creating colliders for assets?

Answer 1

mesh collider. But it is created very accurately, which hurts performance, so, as far as I know, they usually make a simplified mesh of an object for a collider.

Answer 2

1) Read the Unity3D manual on the official website.
2) Download the standard asset pack, it includes the character control you need.
3) All the work is ready, just use ready-made components together.