I use to weigh 600 pounds and now I have extra skin?

Good for you! Be proud of yourself, as I know you are. The extra skin is a problem, but cosmetic surgeons can take care of it. I believe it is called "body contouring." Might want to google that and see what you find. It can be done and you will fell so much better about your body. You've come so far, be proud of yourself! The rest is just cosmetic. God Bless you! I admire you, completely!