It’s fairly well answered by basic information about alcohol serving sizes, DUI limits, and just the amount of fluids someone can take in over an evening. 1 can of beer = 1 basic dose of alcohol. 2 in an hour puts you over the legal limit for blood alcohol for driving. Someone could typically drink maybe a gallon of fluids in an evening regardless of what it is. Beer is sold in packs of 4-12, which are usually shared. So a normal amount of beer to get for someone who isn’t a regular alcoholic would be 2-6 for a night. It also varies with their weight and the strength of the beer (most is about 5% now but some is higher).