Platte River Campground and D. H. Day Campground are both in the Sleeping Bear Dunes Natl Lakeshore. Both have beaches nearby. D.H.Day is near the dune climb.
I do not think that they have camping there.
Go to recreation.gov as well as the website for Sleeping Bear. Pictured Rocks has backcountry camping (permit). Sleeping Bear might but Arcadia is likely a no
I don't know of any at Arcadia Dunes but hipcamp might have something. It is like Airbnb for campers. https://www.hipcamp.com/discover/michigan/arcadia
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