dont know what you can legally drive at the age of 14 in pennsylvania , but i guess the legal age is i believe 16 to drive a moped on the road
like in europe ,with some exceptions
in Finland,Czech Republic, Slovenia, Spain and Sweden its 15 years
in Estonia, Latvia, France, Italy, Portugal and Hungary its 14 years
in Germany you can drive with 15 a restricted moped then called MOFA 25km/h (15.5mph)
but getting some physical exercise in your age can't be wrong with obesity getting a problem for many of your age group
you could always ask your parents to move to europe i suggest Germany if you are able to speak pennsylvanian dutch ,you wont even have much problems with the language , if you move the south western part called Palatinate(Pfalz) then you can drive something motorised legally on your next birthday...you just need to convince your parents