First you need to learn how to do basic maneuvers. Best way to start flying is practice range, there you can fly and adjust your settings. To begin with as I said go to Practice range, and do these settings CONTROLS -> BASIC -> vehicle stick aim sensitivity = max (100%) -> ADVANCED -> plane control sensitivity = max (150%) - > BASIC -> vehicle mouse aim sensitivity I use 17% but this is adjustable and depends on preference (you can try higher/lower sensitivity). Then to get used to it earlier than later do this SETTINGS -> CONTROLS -> ADVANCED -> decouple pilot freelook = ON ( you can also assign keybinds to where you want to look instead of using mouse). After settings hop on plane and practice basic maneuvers, you can look up on youtube, but its all based around circles and variations of it.
With mouse you roll airplane to sides and up/down. With keyboard w - increase speed, s - break, a and d - rudder. I keybind pitch up on spacebar, and pitch down v (spacebar and v are close, so its easy to use them with my thumb). When shooting at ground targets, I use mouse to target up/down - bullet drop compensation, and rudder a/d for plane and target movement compensation. When dog fighting (plane vs plane) rudder (a/d) used for slowing down and plane angle, spacebar for looping, and mouse for changing rotations/aiming.
Total flying time 250 hours and that's with maxing all planes and learning how to fly. Anyone can learn how to fly, but it needs time and patience. Default settings on airplanes are REALLY BAD, so if you have questions, I can answer (if I can).