How do I go about building a dome room?

I am new to Unity and I have the basics down with everything, but I would like to build a Dome structure that is a room/level.

I want the scene to be inside of this dome and be able to texture the inside walls of the dome or apply a skybox type of rendering and also have collision where nothing can pass in or out of it. Is there any way of doing something like this?

Thanks!