New to shotguns and have some questions about my versa max

I have never owned a shotgun before and I've been slowly getting into hunting over the past few years. I don't know much about shotguns and haven't shot one since my grandfather had me shooting paper targets with a 20ga about 20 years ago. Thanks to Gander Mountain closing, I was able to pick up a Versa Max Sportsman in 12ga with a 28" barrel.

If I want to hunt deer with it, what choke would I use with buckshot? My state does not allow rifle hunting for deer. I'm hoping to do some pheasant hunting in the local area as well. I'll try to add a photo when I get home from work.