What to do if the German shorthaired pointer puppy is biting?

I would suggest positive reinforcement. This means when a dog does something you want it to, you give it a treat. And, if the dog does something bad all you do is say no in a stern voice. When a dog sits, say sit and give the dog a treat or praise. Do this with whichever commands you want to teach your dog. Stay takes a long time, you have to say stay, then go a little bit away(like a step) then go back and give praise and slowly get farther and farther away.