Is there a beach at ft.pulaski

No beach.

There is a beach there but it is not obvious. It's about a half mile walk from the fort.

Tybee island is a few mins from the fort

No public beach there. But there is on Tybee Island which is just minutes away.

You'd want to drive into Tybee to go to the beach there. It's maybe 10-15 minutes from the fort.

There's a swamp near by