How can I show my dog who's boss and make him stp attacking me ?

Your puppy is only 7 weeks old. At this age he's not attacking, he's playing. He's also too young to be away from his mom and litter mates at this time. How long have you had him?

Puppy teeth can hurt. At this time, since he's still very young, redirection would be the best course of action. When he gets too playful and starts nipping, a firm no, and than redirect him to a toy, or simply get up and walk away, ignore him. Let him know that there are things he's allowed to chew on, and things he's not allowed to chew on. If he chews on you he'll be ignored, but show him another alternative with a toy.

Positive reinforcement is very important. When he's behaving lots of praise.

He's very very young. It will take some time for him to learn this, so patience is key.