Let me make sure I understand:
First, are you asking if you can play online with one of your friends while you play an episode as they play the original? If yes, then this cannot happen. You need to play the exact same game to be able to connect online. Second, if you are asking if all the cheat codes from the original are available in the episodes? If yes, then this is correct. All vanilla GTA IV
cheats are available in both TLaD
, in addition to exclusive ones for each too.
Hope this helps.