Becoming a cyclist was inspiration for me to get into shape. Hopefully, it will for you too. Riding is great fun and great exercise in getting toward being more fit. A change in diet is just as important. I was overweight for 20 years, and any diets I tried didn't help. But once I got into cycling I was inspired to eat right and I made it stick. This is a common cyclist story, and hopefully it will become yours. As for the hardware, I think all the suggestions given here are good. Main thing is to get pedaling.