Just start out small so you don't get overwhelmed
For example when I started out to lose my weight before the wedding, I started out *just cutting out jelly on my bread. So i'd just have bread and butter. Since the jelly was something I used to eat ALL the time, cutting back on that probably cut out 50 calories a day for me.
Then after I got used to no jelly I cut out cold cereals. Since I was eating like 5 bowls of cereal a day at times that cut out a LOT of extra calories,and in place of that I would eat veggies/polenta/skinless chicken breast.
look at what is in your diet that you can start cutting out and then go from there...
(Now that I've lost the weight and maintain it with exercise, I eat my jelly and cereal, just not nearly as much as I used to eat)
If it overwhelms you to think of working out for 20 min at a time, try just 5 minutes at a time,3 or 4 times a day...stretch during your tv shows, march in place, that kind of thing.
You can do it...remember slow and steady wins the race!