Legal Question in Civil Litigation in Georgia

You didn't tell us what type case this is but you are WAY over your head and need a lawyer yesterday. This is no more something you can learn to do in an internet post than removing your appendix.

Since this happens late in the game, your question tells me that you didn't even do the minimal prep some pro se litigants do because you'd at least know what it is. A pretrial order is going to determine what you can and can't do in the rest of the case, what discovery can be done, what evidence gets in, etc. Plain and simple, if you don't get it right, you've already lost the case.