4 yr golden retriever grew up with one dog in 10x10 kennel?

He grew up with his dad in a 10x10 kennel. No training. He was active in the kennel and I'm sure he has never been in the house. I have had him for 3 days now and he has not left my dining room. I have other dogs and he is comfortable with them. He smells very bad and needs bathed but he is so timid I have to carry him outside. I don't want to rush him. I know it will take time but I want to make sure I do this right. I don't want to ruin this dog.