How do I lose 20 pounds in 3 months? Without pills or drinks, only with a treadmill and a cycle. How long would it take and how many times would I need to work out a day?

Eat less. You can lose weight by eating about 1200 to 1500 cal per day. Exercise helps, but if you exercise too much, you will gain muscle and not lose as much weight. Eat small healthy low fat meals and go for walks or a 30 minute daily workout.