Sorry to ask this, but:
I am trying to make my own game. But when I try to delete a civilization, it demands that I add "76 lines" or something like that. Could anyone help me?

You shouldn't delete the barbarians, else the civilization which replaces it at the top of the list in the editor will become the new barbarians, and they'll need 76 "names" in their city list.

Yes, the first civilization is always used for the barbarians.