I’d like to view pictures in Retropie.

Why? I’m always confused on the controls that I can (or must) use on a platform. Some consoles had very “modern” controllers and therefore use almost all buttons and pads on my controller, and some had close to none. To remember what I can do in a game I always watch a picture of the original controller of the platform. I’d like to be able to do that in RetroPie.