just to put a shout out to the civilian flight sims out there, Either Flight Simulator X or the most recent version of X-Plane are the go to civilian flight sims. Very few flight simmers consider Microsoft Flight to be a true contribution to the genre but it would be a perfectly fine stepping stone just to get into flight sims, since it is free and is fairly friendly.
There is a huge community out there that still do civilian stuff on the older software and even the Vatsim community which does it "multiplayer" and with real human air traffic control. (Not all airports are staffed, just major ones, and those only certain times. But you're still expected to treat unstaffed airports as if you're following the proper regulations for an uncontrolled airport, even if it is occasionally odd to simply announce that you're going to land at a major international hub and not have anyone file you into a pattern.
Back to the combat, if you're a beginner, I'd stick with one of the free to play options already mentioned, but I'll also add that IL-2 1946 is a great little simulator, if slightly dated. But it's fun as all heck and one of the most realistic I've ever been in. It is a bit tough to get set up though especially if you want to do multiplayer.
As for control hardware, I've tried a lot over the years, and I've found that most joysticks are just a bit too finicky for me to use for any sort of fine control. In Warthunder I use the mouse+keyboard exclusively. Even outside of that, especially in the civilian sim FSX I simply use a 360 usb controller, which works perfectly for civilian flight, but is again, not quite responsive enough for combat. Personally, I think the whole joystick between the legs thing is an anachronism we could stand to get away from and only really had relevance for planes that had mechanical linkage controls directly from the stick to the control surfaces, but some people prefer it and manage to do quite well.