If i had a driver´s licence / a car..

If we had a paise in Denmark, about "children" on 16 years could take drivers license, will i take it, when i could. But i can't understand that, in USA must people drive a car, as they not must touch alcohol before they are over 21 years old,  it makes no sense!

If i had a car now, it will do all things easier, because i could drive every where, i want!