I was 18 and weighed about 280 pounds and realized I needed to change, working out, more water, and generally eating less helped me a TON I now weigh about 170.
I look back at when I was 280lbs and losing over 100lbs now has really changed my life. It's not easy, the reward is well worth the work. Start small at first, eat a little less and make healthier choices. Cut down on the soda that you drink or cut it out completely. You'll see results. Just don't make your goals ridiculous like raider. I'm not sure how bad your pain is, but if you can, lift weights.
This is a picture of me a month ago and a picture of me at last years BR Roadtrip. 170lb(about 15%BF) and about 225lbs(35-40% BF). That's just 225lbs.....imagine 280lbs.....I'm overall just way more happier now.
Good luck to you man!
Also FIsh Chris......4000 just for maintenance.....HOLY SCHNIKES! Also,