How much does Dental Insurance Cost in Chicago Illinois. ?

"Our parents possess a 2004 chevy trailblazer and a caravan. If i were to have any kind of 4 cylinder car. Would it be cheaper to become included to theirs or just to be on my own insurance . I am 16 rather than 17 til may"Im 18 years old. I've never had insurance before because my parents haven't had insurance