
Hi,
Do a "Search" (top right-hand corner of the board) and type in "Mouthing" and you will find loads of previous threads on this, with tips on how to deal with it. Remember it's a normal part of puppy development, and they do grow out of it, but there are ways to make it easier!
I would suggest you buy a copy of "The Perfect Puppy" by Gwen Bailey, as this will give you a lot of very useful information and tips on housetraining, and all other basic training.
Good luck