new to fishing and I have a beginner's question...

I have a question for people who know about salt water fishing....

I just started going fishing and enjoying it a whole lot ( I know, its
very strange for a female to go crazy for it), but my experience so
far has been going on a big drift fishing charter boat where once you
catch a fish, basically the 2 deckhands on the boat come and take the
fish off the hook and either toss it back if its no good, or take it
in and rebait your hook for you ( I assume this is mostly for your
safety and not so much because they want to do that for you, some
people were rebaiting on there own when the guys were busy). My
question is....what are the rules for determining if a fish from the
ocean is edible or if it has to be thrown back? I live in South
Florida so fishing for me is always something to do....I want to do it
on my own though without be supervised by a charter deckhand.

Any advice for this beginner?

By the way....this groups posts have been fabulous for people who dont
have too much experience to read.