Only one loop of the campground allows dogs - besides walking on a leash that's all you can do in the campground. However there is a large enclosed dog run in the park itself (past the campground) which you can access for free if you have a camping pass. There is a designated dog beach area behind the dog run where dogs can run off leash. It's very nice. It's on Google maps - Fort De Soto Dog Park / Beach https://maps.app.goo.gl/HqXHWFeamASTxunh7

Yes, they are allowed but not on beach front area. They are allowed in the back area where there is a field behind the campsites. Unless you can grab a spot that is close to the point then water access is easier. You can not bring your dog to the water. They are very strict on that. Being a local of St. Petersburg I have even seen the Rangers make people leave. Service dogs only at the water. You can walk them anywhere else. I wouldn't let my dog in the water there anyhow. There are gators in the mangrove areas all over Florida.