Some of my personal favorites are Ginnie Springs for the easy entry level access and camping sites along the river with access for kayaking and tubing to keep even the non-divers entertained.
I also enjoy Blue Grotto for the depth and easy access cavern along with some excellent facilities (bring the charcoal and burgers).
Troy Springs is another good entry level spring dive located in a state park environment.
The advantages to the springs are no boat ride, no waves or seasickness, easy shore or platform entry, no after dive gear rinsing is required since it’s freshwater, short walking distance to actual dive site is usually less than 100 feet away from picnic benches and most if not all have showers, bathrooms and changing facilities.