Male Rottweiler puppy won't walk on leash
Growls , flips on his back and when I try to make him move.
Actually growls and shows teeth. Very embarrassing. He's just about 10 weeks.
Your puppy is clearly not enjoying his leash training - but this is perfectly normal. His reaction is just his way of trying to 'warn you off' in the hopes that you'll forget all about the leash that he dislikes so much. You must not let him win this argument!
At 10 weeks old he's just a baby, and you have to show him clearly, firmly but lovingly, that you are in charge and that any growling or nipping will NOT be tolerated. For advise on dealing with nipping and biting check out my Stop Puppy Biting page. This sort of behavior is normal but it is much easier to correct now when he's small (and so are his teeth) than when he's bigger, stronger and has already learned that it works!
I'd recommend that you read my Leash Training A Puppy page as it has lots of tips and advice to help you. I know it's difficult when your pup is resisting, but try to make this a positive experience for him and reward him every time he is going forward with you. If he lies down and flips over on his back, you back up several steps then jog past him calling his name in a happy upbeat voice and show him a treat, or a favorite toy, as encouragement. Chances are good he'll jump up and follow you... then you praise him and give him his treat or toy.
I'd also recommend enrolling your puppy in a basic puppy obedience class, it will help you to understand each other better and you'll get hands-on help with problems such as these. The socialization aspect is also very valuable for your pup.
Hope this helps, best of luck with your puppy.