Florida requires you to have valid insurance for each vehicle. You need to register your vehicles within 10 days of establishing residency. The Florida Department of Highway Safety and Motor Vehicles has excellent FAQ facility which will let you know what forms and validation you need and where to take it for registration. The section of their website that deals with this can be found at http://www.hsmv.state.fl.us/dhsmv/newflres.html
If you driver’s license hasn’t expired you can probably convert to a Florida license without a written test. To check and to see other requirements, go to this web page http://www.hsmv.state.fl.us/ddl/faqkeys.html