Camping fees can be paid in cash at the fee station on Buck Hall Landing Rd or online, where you can reserve the tent or camper sites that allow it. Unfortunately, I don't know what the URL is, but you should be able to find it doing a Google search for "Forest Service Campground reservations" or similar. If you are asked which USFS it's in, use "Francis Marion National Forest".
Where can you get firewood?
Either by online reservation or pay at campground.
Ditto
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