Your first port-of-call should be the wiki, if you haven't already been there. Sadly, a lot of the information is outdated, but it's still a good place to start to read up on the extended lore.
Next, browse the Official and Unofficial Factions subforums -- there's more lore, and you may find playergroups you'd like to join.
Yes this server is a whole lot different from the single player, and I know it’s daunting, but your best choice, is to try to get your head around the rules HERE
Basically most of it is to just play fair, learn your possible future characters ID’s and the Roleplay behind them
Think of a character you wish to play
Search for existing and previous posts, gain knowledge and above all ask questions of their leaders on how they play that ID/Faction
Above all have fun
We will see you among the stars
(if you want banners or any graphical stuff done etc etc just ask, there are good few here, including myself)
Welcome to Discovery, Big thing to take from this. You can do what ever you want. Take something from Freelancer and focus on it. Its fun when you really get into the grit of the Role Play.
Just as the constant increase of entropy is the basic law of the universe, so it is the basic law of life to struggle against entropy. - V. Havel