Well, do you want to fly military or civilian aircraft? There are different jumping-off points for each, because each has their own simulation software (Microsoft’s flight sim is geared towards civilian aviation, other games like Lock-On or IL2 are geared towards military aviation) - the catch is that most military fighter games don’t put a heavy emphasis on aircraft systems, and aspects of aviation like navigation - they’re not necessarily accessible to players or necessary for the game, so they’re omitted in favor of other features. There are some upcoming games that should fit into that niche, but until then, you kind of have to pick sides…
If you’re interested in the aviation side of things, I strongly suggest getting a copy of Microsoft Flight Sim 2004/X (depending on what your computer can handle) and learning the basics there - instrument and visual navigation, maneuvers, takeoffs, landings, (simulated) radio communication, and instrument approaches. It’s easier to practice all of these in MSFS which has a more relaxed flying environment, than another game which drops you into a combat scenario where people are also shooting at you when you’re trying to learn.
If you’re interested in the combat/gaming side of things more, I suggest getting a copy of Lock-On, printing out the manual/control reference, and flying through their tutorials until you get the hang of things…they explain maneuvering and how to fly the aircraft and use the systems extremely well.
If you have any specific aviation questions, feel free to ask - I’ve been flying simulators for years and have a number of hours in the air as well 