Hi Christopher! Welcome aboard!
Coral World Ocean Park is one of the places I really want to visit on our next port stop at St. Thomas. As you'll see on Disney Cruise Line's website, there are a few different Port Adventures available that go to Coral World. If you're looking to just have transportation there, time in the park, and transportation back, your best bet would be the
Coral World Ocean Park and Scenic Drive Adventure. This includes the drive there, time at the park, including your admission and a coupon for nectar to feed the birds, a scenic stop on the way back, and that's about it. The other two Port Adventures include other add-ons.
You always have the option of finding and booking your own transportation there and back, which would mean you need to pay for your own park admission as well. When Disney offers a similar Port Adventure, I usually recommend going with theirs, as they've put a lot of planning into these Adventures, and know the tricks to getting you there and back with minimal effort on your part.
I hope this helps, Christopher. Good luck with your planning, and enjoy your cruise!