I have a 10 mo. Old male yorkie and he eats but not a lot. He is very active . But he is so skinny you can feel his ribs and back bone . He weighs 2lbs what can I do

Has he been dewormed recently?
When was the last time he saw a vet?

I agree with Sariss, making diet recommendations should only be done after he has been seen to by a vet to make sure there is nothing medically wrong with him.