If sports betting age laws in your state say 21 though, that is the rule to follow.
Failure to do so will result in forfeiture of said winnings.
Some states do have prohibitions against social betting with somewhat archaic laws.
States do not enforce social betting laws unless there's other criminal acts.
You likely won't face charges but your money could be at risk of government seizure.
You don't have to be a resident of that state, but you must log in and bet from their jurisdiction.
When Will My State Have Legal Sports Betting?
Unless you live in Utah, soon.
faux saint laurent bag