hi welcome to YT!
sounds like your puppy is quite smart with learning tricks so he should get the potty training thing soon. Does he go outside as well as inside on pads? maybe he is confused. i only trained mine to go outside so i don't have any pee pad advise.
to stop him from biting you can try replacing your hand/feet/whatever with a toy to chew on. when he bites you tell him no and give him something else. Or many people have had success with this other method. Whenever he puts his mouth on you yelp really loud like it hurt you. Pups will play bite with each other but when one yelps the other will stop biting. if you do it every time he puts his mouth on you no matter how hard he bites he will think that we humans have very sensitive skin and can't take any amount of biting with it not hurting.
__________________ Kellie  and  Morgan |