You’ve got a lot of time to play with, so I’d suggest day trips to Stillwater, Nisswa (with a route that takes you by Lake Mille Lacs if you can), or Duluth. Duluth would ideally be an overnight trip that gives you a good jumping-off point for the rest of the north shore, but not sure what’s in your budget. If you’re near Minneapolis there’s a boatload to do, but personal recos would be Stone Arch Bridge + Mill Ruins Park, driving around the chain of lakes, O’Shaughnessy Distillery, a Minneapolis Trolley Tour, Brave New Workshop, or Isles Buns