Hey....... welcome to hunting! Who do you have to take you out?? Is it your Dad, or another family member? You will probably have to hunt what they are, as 11 year olds can't hunt with a firearm by themselves in most states.
Did you take hunters saftey yet? Do it......... it will teach you a lot about guns, hunting, using maps and compass, and how to be safe in the woods.
All of those things you mentioned are lot's of fun to hunt........ but you may not like them as much at first. You have to be REAL still and quiet for all of those animals. Deer and turkey for sure!
If I were you, I would start out with some small game hunting and see how much you like it. If you get good at rabbits and squirrels, you can hunt almost anything!
The 20 ga shotgun is a good all around gun for you. You can hunt all kinds of small game with it, and waterfowl, deer (slugs will be best) and turkeys it will work just fine.