Why is my player moving around and shaking on surfaces?

I have imported a random town from the asset store but when the scene opens, the player starts shaking and bouncing around the town.

Is there a way to fix this?
I am doing this in 3D.

What type of collider does the town have - I dont know about that but it should have a non-convex mesh collider (set the convex in the mesh collider to false)
Other than that try disabling rotation on the players x and z axis in the rigidbody (if you are using a rigidbody system for movement)

Also, where its a new scene, Bake NavMesh…