they drive left and a tad on the reckless side
can't say about restaurants, sorry--it's been a while
there are "buses"--open truck shuttle you can stop anywhere on main roads for transport
I can recommend HawksNest Beach (no potties) but gorjus swimming--frequently private
Megans bay is the commercial beach that used to have some decent restaurants--beach fare
The National Park is good for snorkeling--they rent everything from chairs to equip plus admission fee--showers, changing/locker room etc
Island is small--maybe rent a car for a day--go into town and rent there--they charge plenty to bring you one to resort

They can take a ferry to nearby island for day trip, too