If his teeth are barely in , he's definatly younger than 11 weeks. It's not your fault, but you definatly got a dog from a bad breeder. He was too young to leave him mom. As was said, he does need to eat every few hours for now and will be very dependant on you for a while. I wouldn't even focus on housebreaking too much yet, get some piddle pads for now, he's just not capable of grasping too much of that yet and will have to go very often regardless. I agree that if he'll eat the baby food, feed that for now and try mixing it in with some mushy canned dog food. You can worry about a high quality dog food in a few weeks, for now it's more important that he just eat, and baby food isn't a bad option for a while.
No sausages or anything else high in fat. If you have a food processor, you can boil some chicken breast and then grind it up and see how that goes over with him.
That's all I can really tell you other than contacting this breeder and complaining. She obviously lied about his age. I agree too that you should re-post this in the breeders section, you'll get more specific experienced advise there
. Good luck