Ask the multiplayer forum down below this one.

Vatsim has a lot of information for new pilots and can be a lot of fun. The most important thing here is to make sure when you go online with Vatsim that you let them know you are a new pilot and this is your first time flying with them. If you do not let them know you could be in for a rude experience. Vatsim is as close as you will ever come to actually flying using ATC they expect the pilots to be knowledgeable in all aspects of flying . As for a virtual airline I have belonged to several and this can be a great place to learn as quite a few of them have there own ATC and are more forgiving. It can be a great experience or a complete mistake. It is up to you every one has different desires so make sure you check out the Virtual airline before you sign up.
Here is the link for Vatsim http://www.vatsim.net/ ;