I would steal my dads liquor when I was 14-17. And my friends stole their parents liquor as well. We got a couple adults in my friends family to supply us as well a few times which is pretty messed up on their part but oh well.
We didn't get caught because we usually did it at my friends dads house and he was really oblivious and often drunk himself.
I was also slick af lol. Um now, I have friends who are 21+ up to buy me stuff but I rarely drink. When I do I don't have to hide it bc my parents don't care.
Parties... Unless you don't get invited then most places will ask for ID. Another option is if u have an older sibling or friend. Also why do u think ur parents will catch you? Unless ur drinking in your own house.
It was pretty easy: -befriend someone older than 21 -get them to buy you alcohol -drink it in moderation, my family didn't really notice I was buzzed. All I did was eat pizza crusts and other munchies.