Why are you dropping out of school and compromising your future for a job at a supermarket? Anyway, selling alcohol is completely haraam. "When Allaah forbids a thing, He forbids its price (buying/selling)." (Musnad Ahmad) Anas ibn Malik narrated, "Rasoolullah cursed ten people in connection with wine: the wine-presser, the one who has it pressed, the one who drinks it, the one who conveys it, the one to whom it is conveyed, the one who serves it, the one who sells it, the one who benefits from the price paid for it, the one who buys it, and the one for whom it is bought." (Tirmidhi)