The best thing to do is simply exercise and eat correctly on the days you can. I am over weight but have recently lost 20lbs just by following those to simple things. I know it can get hard, but don t give up! Breakfast is of course the most important meal of the day so DO NOT skip it. Actually, studies show that eating breakfast can help you lose weight in the process of weight loss. If you must skip a meal make it dinner. Also don t eat after 8 or 8:30 pm. Exercise is also important. The days you CAN exercise make sure its at least a good hour (cardio can be for 30 mins). Good luck I hope I helped!
Working out on a bike is a good idea, but unless you watch the calories in your food, 10-15 pounds will be hard. For more tips, go to tummywatcher.com