Yes, No, Maybe
Jackie, It is good to add sugar to the Brix level that you desire that corresponds to the correct potential alcohol level. If you want an average 12% alcohol wine you need to sweeten to 21.5 Brix. (percent sugar by weight). This will give you the desired alcohol. I use corn sugar, this is really easy to dissolve, if you want to use granulated or regular sugar. Put it in the food processor for a few seconds to get it into small granules. this will make it easier to dissolve. And make sure to make a yeast starter culture while you are doing any additions or modifications to your juice. By the time your done with those you can pitch your yeast, put a fermentation lock on and sit back and watch a fermentation happen!!! Have Fun. And most of all, Relax, fermentation is easy!