Why is my Doberman puppy biting around, he even bites me

I have a 7 week Doberman puppy, he is always biting around, he bites me quite often,and always tries to attack me. I was told that it was quite norman for a puppy, I am wondering how long it will take before he stops biting around. Thanks.

By the way, I also found he always scratch himself, I did not see any flea.

Puppys chew because they are puppies. He will soon start teething, and like a human baby, it hurts and chewing helps. Get him one or two chew toys, and any time he chews on the furniture or whatever tell him no, and give him his chew toy. When he starts paying attention to his chew toy, praise him. It'll take a little while but he'll figure it out soon enough.

As for biting and "attacking" you, he is probably trying to play with you. It is actually useful for him to bite you at this point. You can use this time to teach him just how hard to bite (not very hard at all). When you are playing with him and he bites you, pay attention to how hard the bites are. Pick a bite that is a bit harder than most of the rest of them, and then act like he hurt you (even if he didn't). You have to do it like a dog though, because that is the language he understands. Yelp (make a sound like he might make if you stepped on his foot or tail) and then turn your back on him for about 30 seconds. If he comes around in front of you, turn your back again and don't make eye contact until the 30 seconds are up. Then, have him "apologize" to you. This might mean he has to sit first before play can resume.