Go and buy yourself a copy of "South Beach Diet". There's a lot of good information in there, and it's more about a long-term food plan than a specific diet to lose weight (though there is an initial phase). If you start getting serious about biking (ie riding more than an hour multiple times a week), then you will need to make some modifications. I use a modified version of this, and if you eat the right foods, you can be satisfied even if you burn more calories than you eat.
I'm not a big fan of diets that have you eating something other than real food, as it's too easy to go back to your old habits. What you need to do is change those habits. The details are in the book, but the simple story is that the more refined the foods are, the worse they are for you. That means getting rid of white flour, white rice, white sugar.
I think initially, you should ride 3 days a week. You should do an amount where at the end you feel energized and perhaps a little tired, but not dead. That might be 15 minutes, 30 minutes or an hour. It's really important not to overdo it - you're trying to burn calories and improve your aerobic capacity. You should be able to talk easily at least 95% of the time you're out. Make sure you resist the desire to ride really hard.
Once you tolerate that, you can add days, or add an alternate activity such as walking on other days.
Once you are doing an hour several days a week, you can start riding harder. At that point, you will need to explore recovery nutrition.
Good luck, and let us know if you have other questions.