That's a long drive! There's two main ways to take it. You can go under, or over the Great Lakes. If you go under (about a 17 hour drive) you'll probably want to cross at the Port Huron-Sarnia crossing from Michigan into Ontario. If you go over, though, which is a bit longer at nearly 19 hours, you'll cross at the Sault Ste. Marie border post, which also goes from Michigan into Ontario.
There isn't really a practical route that crosses directly from Minnesota to Canada. The nearest would be the Grand Portage-Pigeon River border post, but that route takes you up through Thunder Bay and is nearly a 24-hour haul.