You willfind that ND is very freindly for duck huinting. If wiull aslo likey find most land is posted. It is correct that most land ownsers are pretty nice about letting you hunt. Some are not, but thats why you ask. ND offers plenty of water to hun tover or on as well as field hunting. reallyit is up to you as to which you. I prefer the field and have hinted exclusivley in feilds for the lat 20 years. If you are gona hunt in the fields I reccomend at least a few dozen full body fullmotiion decoys. Shells work, but you will draw far better with some motion and full body decoys. You will likely want a dozen or two of full body full motiion canadian goose decoys if you dont own them as well. Shells work fine, but the motion is killer. If you dont own a robotic decoy, I would reccomend one of those iof not two or three, with remotes if you want to shoot canadian geese. Lay out blinds are a must in the fields as well.
You really need to do some research into where you want to hunt. You can hunt on the river out west ( missouri), or the canadain border big lake area like Devils lake or the opposite side of state Minot and up there, or the midddle prarrie pot hole region, dead center of the state basically. All three are great and will give you plenty of opprotunity if you do the work to find the birds and the land to hun tthem on. Thats what it boils down to, doign teh work to scout, finding the birds, and secure the land/water to hunt them on. Good luck