What is ethanol and intoxicationmg mgs?

I'll answer half of the question.

Ethanol is the alcohol that is in alcoholic beverages -- liquor, beer, wine, etc.

There are too many variables to answer the second part of the question. The amount of ethanol necessary to intoxicate depends on the concentration of the ethanol, the weight of the person, whether they are male or female, what they have eaten before imbibing, their tolerance to alcohol, etc.