I live in central Florida and travel and camp in the keys pretty regularly. The Keys can be a tricky place. Most people love it or hate it.
https://jrtp.com/ - Nice park all around, especially if your a boater which we are. The seven mile bridge pilons are tremendous fishing spots and if the weather is rough on one side of the island you can launch on the other side of the island. You can catch 50 pounders around those pilons. all deep water.
https://newbook.rvonthego.com/search/?search_type=region&show_parks_near=Florida+Keys+-+Key+West - Fiesta Key is the best water I've seen, but a little too touristy for my likes. Sunshine is my usual go to in Marathon. Not touristy but very, very Hispanic which means they all go home to Miami during the week and you have the place to yourself.
I don't go south of Marathon because I don't like to camp and resort in the southern keys. Personal preference. But if you are interested...
There is one place a little further south called Big pine key campground and Marina. No pets because of the key deer and although beautiful the water it is rough.
If drinking and partying is your thing then go to Geiger key marina campground and local bar in key west. Beautiful water but little access to calmer seas.
Beverly Beach campground in Flagler beach up here by me is the nicest ocean view you'll get in the state of Florida.
If your into bass fishing and camping any lake and river will do at 5 am. the water is really nasty inland.
I know it's a little more than you asked for but that's where I usually go.
Any state campground in Florida is a year out unless your the luckiest person on earth.
I lived in Binghamton NY for half my life and the finger lakes have tremendous opportunity for camping. 1000 Islands up by you is gorgeous summer and winter. Also have you considered a small tow behind? they are cheap super light these days and you can leave them and travel around. All the storage you'll ever need. Not trying to talk you out of a truck camper.