Okay, than first and foremost read the included orbiter.pdf you will find in \doc directory of your Orbiter installation.
Read it for two reasons:
1. To get acquainted with the concept and instruments of Orbiter. It's not a flight sim, and even less so an arcade
game. So you really have to understand certain concepts intuitively before you can have fun with it
2. There are quite a number of tutorials there already, to get your from Earth to space to International Space Station.
Then go here:
http://orbit.m6.net/v2/read.asp?id=18152or just browse the main forum to find discussion that you'll find interesting.
Cheers,
Janez