jail is where they’d put you to dry out, sober up, hopefully behave yourself. lots of old movies make jail seem comically quaint. I myself have been released from the lockup “on my own recognizance” or some such, basically means they didn’t want the expense of keeping me there, plus I agreed in writing to show up for the court date.

prison doesn’t have to mean federal time, could be a big scary state prison, but you get there from doing felonies. and the felony could be just weed, like you had a garbage bag full of it and shared it with friends.