You have a couple of options for camping at Lake Superior Provincial Park.  The first is at a campground, the second is a backcountry site.

If you are wanting to camp at a campground, you have 3 choices from south to north; Crescent Lake, Agawa Bay and Rabbit Blanket campgrounds. You can see their relative locations on the park map.

If you wish to camp at a backcountry site....

Lake Superior Park Map