Depends on a lot of factors, but for easy, safe beginner diving I’d look at going to some of the Florida springs. Most of them are crystal clear, and its shallow water diving in a contained area so lots of down time with no current or need to navigate. Just be sure to educate yourself on not going into caves. You can plan a day, or several days, and hit several spots in a single day and they’re all very different. All of them are great to visit in the off season when the crowds are down. Some you can dive…some only allow snorkeling. A few good ones I can remember are drift diving in the Rainbow river, Ginnie springs which is actually three springs along the Suwanne river, Devil’s den, Salt Spring which I believe is snorkel only, and Vortex which is in the panhandle which has a beautiful cavern entrance with limestone formations.