I am trying to find some new places to go duck hunting int eh outagamie, calumet, and winnebago counties. I am looking for public/private land to hunt.

Anyone who knows any places that produce well let me know it would be greatly appreciated

My brother hunts in Prairie Farm WI.

What kind of training do I have to do? I would appreciate any information anyone can give me on the subject.

there really is no formal training. you have to know the animal well, the area it lives in, it's habits, mating cycles, calls, etc.etc…….
I'm sure you could get on as an apprentice in a guides territory and spend a few seasons learning from the other guides. there is so much you have to experience to learn that a lifetime of knowledge will get you. i learned from my father and uncles and i still get fooled all the time.
best of luck

My dad has a 12 gauge that supports 2-3/4" and 3" rounds. Which is the best one to use duck hunting?

winchester Xpert 3 inch number 3s if you have a lot of pass shots and high flyers go with number 2s get the heaviest shot charge you can and MAX powder