Welcome! I still remember when I thought that 8 miles of road biking as a lot. You'll be surprised how much you can improve if you keep at it.

One thing that I wish I had known at first, granola bars and energy bars have tons of calories. Now, I only have half of a granola bar or Cliff bar after one hour of riding along with drinking electrolyte fluids every 15min.

Hope you fall in love with biking so that even when you do lose the weight, you'll keep it up.