As it was said above Little Nav Map is essential. Because it:
a) lets you decide from where to where to fly and quickly zoom into the airport to see if the runway is long enough for your aircraft
b) shows you the progress of your flight on the map as you move along. If you get disoriented you can see which way to turn back to where you were going
Once you have decided from where to where you want to fly you open the world map, enter departure airport. then the parking gate. then the arrival aiport. then the type of flight. (VFR, IFR hi or low) Then select the departure procedure (SID) Not really necessary in the beginning.
- I would decide on one aircraft for now and practice with that one.
- choose one with an autopilot, it gives you more time to check things and prepare yourself for whats next in the flight without having to worry about trimming the aircraft all the time.
- find a short route ( I did Vancouver - Seattle I don’t know how many times) and fly that repeatedly. It makes you more familiar with the aircraft and the route of course. ( familiarity is key)
- do not worry about things like TOGA at the beginning. In my close to 3000 hours I did the take off and go around (TOGA) exactly one time. and you can instead always push the throttle to take-off power, retract the gear and suck in the flaps. Its very similar
I fly the CJ4 mostly on Vatsim and for this aircraft there are plenty of youtubes available. ( just search MSFS CJ4 programming the FMC for example) I suspect there are youtubes for other aircraft types as well.
Hope this helps a bit.