how do i rotate things?

even though i know alot about Game Editor there is still alot i do not know, like how do i make objects rotate? lets say i have a guy standidng on the ground there is an object above him, how do i make him rotate to shoot at that object, and how do i make him shoot at angles, i know how to make the bullet but the vital thing for me is to know how to rotate things. thank you if u do post anything