Welcome FlyingBird!
Before you can start flying, you need to set up your Joystick! Go here
http://www.netaces.org/joystick.pdf to read how. If you do not have a Joystick, youll need to use mouse to fly (possible, but not recommended). You can find help on how to set that up on this
http://www.slowcat.de page.
Also, to start out, i recommend you at least change the loadout (fuel to 50%, NO rockets/bombs) in HANGAR. That will make control easier.
If you go to
http://www.netaces.org, you can find a Quick Reference guide. One page to print out with all the default key commands. Apart from that, net aces is a great spot besides the HELP file to make yourself familiar with this game.
When you decided to try ONLINE play, come to the training arena if you need help flying.