I love red wine, which is a type of wine made from dark-colored (black) grape varieties.
When did red wine become popular in history?
The juice from most purple grapes has been used as drinks for centuries! 
How does a wine become alcohol,  i thought grapes are just fruits?
Its a long process actually that begins with vinification, which is the production of wine, starting with selection of the fruit, its fermentation into alcohol, and the bottling of the finished liquid.