Im sure that diet and exercise advice will follow, I want you to do something different first. This will make you feel much better and definitely tighten your waist a little.
Back when I was starting college I was doing the same thing: soda and fast food all the time, diet was in shambles. This didnt last my whole life but I ate my fair share of s###. After a while I realized what I was doing and started to eat right/exercise. BUt for some reason no matter what I ate I was always feeling bloated like you, stomach swelling up after every meal. No matter how much Id go to the bathroom I could never get rid of this bloated feeling. So finally I said f### it Im gonna cleanse my colon and see if it feels any better. This particular cleanse wasnt harsh at all and bro, I completely lost the bloat, 5-7 lbs, and my stomach shrank to normal. As a matter of fact my bodyfat so already pretty low so pretty much right after I got the 6pack ive been rocking since.
I am in no way a representative of this company, just a big fan. They have all sorts of cleanses and help with diet too. I actually bought their "wellness" filter which is a brita alternative. I also got my chlorine filtered shower head through that site as well. The colon cleanse is called "oxypowder" and 1 course of it is all you need. I think its good for you to start with a colon cleanse because if its bloated/clogged, then you are not absorbing nutrients well and a diet/exercise program won't be as efficient. This made me feel like a million dollars and since you have been eating poorly for a long time, it will do the same for you. Disregard this advice if you want, but I think a cleanse first is exactly what you need. Combined with a good cleansing diet (apples,spinach n greens, water, apple cider vinegar, etc) this should really help you and get you ready for good lifting/good eating. The website is :
global healing center I think its called. the instructions are all there. and this is the link to where the diet is:
Let me know if you have any questions, but seriously if the bloating is bothering you this is the best thing out there. Fast food and other crap food doesnt digest well and just sits in your colon, like a brick. Im sure other people are going to post foods and supplements but this will give you a great foundation to build on.