You could still enjoy Maverick but......talk about being totally lost on the nuance of the actual plot vehicles and inter-personal interactions.
Do NOT attempt to watch Maverick without having experienced Top Gun.
Cool story bro: I heard about a chance meeting of Tom Cruise and Kenny Loggins in an elevator a few years ago right after talk of Top Gun 2 emerged. Kenny says to Tom, so you think there's room for Danger Zone in the new movie? Crusie just looks at him kinda dumbfounded and says, "Kenny, it ain't Top Gun without Danger Zone." Like, duh, of course it'll feature prominently in Maverick.
If you haven't seen the first one, you wouldn't begin to understand the audience's emotions when that song cranks up in Maverick.