I'm thinking about getting surgery to take my fat away. I'm 18 and the only time I've ever lost weight was when pregnant. Is it a good idea?

Probably not. Even bariatric surgery tends to fail over time. The side effects of bariatric surgery are significant and permanent. You are only 18. You are going to need to take of your body for a long time. At this point you need to have a long and serious talk with yourself about what you really want to do with your life, and then do it! start with counseling, not a scalpel.