So when I select my fighter squadron and I click on a friendly ship, I get a triangle icon. Am I correct in assuming that is the instruction to my fighters to loiter over that ship, spot for it, and fend off enemy air attacks on it?
Yep I call it "orbiting" I usually send a fighter over say a BB and protect him. If an incoming bomber gets to close the fighters go after them.
you can also attach ur fighter to ur strike planes and vice versa, but its kinda bad to do it and only worth it if u are really lazy. Also you can do it friendly cv planes asell but I wouldnt recommend it