Welcome to the forum. September is a great time of year. Is your goal to go in about u or 8 miles, camp overnight, and come back out the same way? What do you value along that route, how much portaging is ok, is there any specific sort of fishing or scenery that you want to see?
Most entry points will work for that, but most would generally be out and back. You'll need an overnight paddle permit and those are specific to date and place, so if you have a specific entry date some entries may not be available. There are several different general areas of the BW - the western area around Ely, the Sawbill Trail area out of Tofte, and the eastern area off the Gunflint Trail out of Grand Marais - if travel or other considerations limit your options.
Will you be fully self-outfitted or need the services of an outfitter? What about accommodations the night before and after?
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