2.5d?

Hi guys, I know you cant do whole game for me and im not asking for that, all I need is just a start afterwards I can look at the code study it, learn form it. Sadly I cant find a tutorial that fits my needs.

What I need, I want a 3d game in where the camera is over you.
You might think, why do I need 3d then? Well, think about a game like GTA 2, its from camera is over you, but you can see the buildings is in 3d. Walls look different depends on what side you stand on. So I need some sort of a box that sands still, a dot that you can steer here and there, and when I move the dot I can see the walls change its look, sides…

Could someone tell me how do to that? Or maybe they have a copy of a just started game that contains function?

I think its called 2.5D, I guess…