Does Call of Duty teach you how to shoot a gun?

Not a real life gun, no. It teaches you how to point a virtual cursor at an in-game object, and push a button on a controller, or click a mouse to shoot a virtual gun, but it doesn't teach you how to shoot a real gun.

You want a tip on using a gun? Line up the sight, target, and the nub at the end of the barrel and fire.