Hi and welcome from a UK clyde,
There's loads of advice and help here and I can personally attest to the effects of getting the cycling bug. I'm a newb myself so i can't help with technical side but I can cheer you on. If you've got a smartphone you might want to get a an app like map my fitness /map my ride to help manage your diet and log your improvement as you go along, also don't forget to talk to your doctor about what you are doing.
Above all, don't worry if your slow at first you'll get better, start slow enjoy the ride and you'll be able to increase speed and distance as you burn off your fat.
welcome again
Billiam
whoops sorry I wrote this before I saw your last reply
