Did you measure the brix of the grapes? That’s the sugar content. That gives you some idea of what alcohol level you will be obtaining (roughly half the bris).
Your first step (other than getting this thread moved to the correct forum, IMHO or CS) is to ferment the juice. To do that, you need to activate the yeast (warm it in water for a few minutes) and add that to the juice. That might take a week or two, depending on how much sugar the grapes have. During that time, you need to keep measuring the bris and tamping the skins down. Tamp them down 2-3 times per day until fermentation is complete.
Your next step is to get a good book. I recommend From Vines To Wines. And find someone local who can help you.
I have no winemaking expertise to share, but I want to say that this sentence made me laugh out loud. (Bris means something very different than brix. ;))
I’m not an expert, but I made many barrels of wine with my dad whan I was a youth. He just crushed grapes and let them ferment naturally. Never added sugar, water, or yeast. It always worked out fine.