I started "drinking" at age 20 in college. Socially always, never alone. Mostly beer and the typical college shenanigans. It wasn't problem drinking. Going to the liquor store was reserved for special occasions a few times a YEAR.
My problem drinking didn't start until I was 27ish. Drinking alone to mask my depression and anxiety.
I guess I didn't really do anything at all before drinking. I was just normal and happy. Odd to think about.