Reduce fat the quickest by riding a lot at a moderate pace, and eat stuff like scrambled egg whites with catsup, plain tuna, plain steamed broccoli, dry wheat chex, that kind of thing. To maintain it, well that's just lifestyle. Get used to eating healthy, balanced meals in small servings, while exercising regularly however, 6 or so hours/week. Or just start doing that latter and get the same result more slowly. Running is good, too. Much quicker than cycling, but with added joint stress. Just depends on where you find your joy. Weight lifting doesn't burn as many calories in just the doing of it. Most folks at the gym who only weight train have a good bit of fat on them, unless they are also very careful about diet. Still, it's a good thing to do. Strengthens stuff like muscles, ligaments, tendons, and bones. Which is all good.