I'm 265 lbs, 30 years old, man-boobs and a beer-belly. Can I join a boxing gym at this age and transform my body to look awesome?

of course you can!! But you won't be able to see much muscle unless you trim the fat first. Try a diet low in carbohydrates: cut out sugars, pasta, bread, rice and fatty foods. You can treat yourself occasionally. But try to have a bigger breakfast and smaller lunch, dinner and snacks full of vegetables, eggs, fish, meats. If you do this you will lose weight quite fast. Muscle assists in burning fat and raising your metabolism also. So combine your muscle building routine with the low carb diet and you will look and feel great after 3-6 months!!

I like to eat low fat, and organic to help with weight reduction. It it is imperative that you do cardiovascular exercises, combine with weight training as well, so it may be helpful to join a gym, or try a much less practical option of buying exercise equipment(the rich man's option).

Try bodybuilding gym for faster results