Must be on a leash. There are some less used areas over on the island (west of Destin) that would be better for a pet.
I do not have a dog and do not know.
You’ll have to do some searches of local area beaches. I’ve found that they are pet friendly and you’re required to keep them on a leash. The problem is that I can’t find anything pertaining to visitors. Residents have to obtain a permit to walk their dog on the beach at several beach in the Destin area.
I know in Brevard County where I live on the east coast of Florida, they have a dog beach and they’re pretty strict. Turtle nests are one of several reasons they’re strict where I am.
If you’re staying in a local hotel I’d ask them as well. I found at the Residence Inn they were very helpful with questions I had.
Get an answer from Residence Inn by Marriott Sandestin at Grand Boulevard staff and past guests.