Help me with muscles please!!?

i need help with my muscles. i am 13 male. average weight, height, size etc. i no im really strong and stuff by my muscles dont even really show it. i work out alot and sometimes after my muscles look like there not even bigger they look kinda the same or even smaller?. there is nothing wrong with me im probably doing the wrong work out so i need help!! what work out would be great for my chest, arm muscles and my leg muscles to get bigger. (i also got a bench press, punching bag, dumbbells and curling bars and a treadmill) and please tell me the right work out.