Starting to exercise is a great first step. Take the steps I mentioned on your other thread first to make sure you are able to exercise. We don't want to hear that you've had a heart attack or anything like that. When you are cleared to start exercising TAKE IT SLOW. Remember the old saying "Slow and steady wins the race." It also reduces the chances of injury. Walking is a great place to start. It's where I started. I measured a 1-mile loop through my neighborhood and walked it. Start with ONE (1) mile, this should take anywhere from 20-25 minutes. Do that ONE mile everyday for a week. The second week increase to 2 miles, the third week increase to three miles.
Your physical fitness will improve rapidly at the beginning and you will be tempted to do more, but resist the urge. Remember "SLOW AND STEADY." You didn't add that 80 pounds in a month, you're not going to lose it in a month.
You can add some stretching to your routine and maybe some calisthenics. There are lots of videos on Sparkpeople to choose from. Pick a few that interest you AND challenge you and do one each day/evening. Remember, you're like me, 80 pounds overweight so the lower the impact the better to start.
Remember to drink your 8 cups of water (or more) per day and watch your meal plan. Calories count in and out.
Good luck and JUICE to you!