Definitely try to meet other singers in your area, and get along to Old Songs festival or the Cornell Folk Music Society (I'm playing there myself next year).

If you want to go into it more deeply you might enjoy a summer camp like Augusta Vocal Week (West Virginia) or Swanannoa Traditional Song Week (NC) or Goderich Celtic College (Ontario) where you can learn a lot about old songs and singing. Not cheap, but they might have scholarships available for someone of your age.

The best thing is definitely to get together with others who share your interest. It is a great experience to sing in a roomful of people who all love singing as well, and it can be very moving to have people join your chorus for the first time. It's true that many enthusiasts for folk song are of the generation above your own, but there are young singers to be found at some of the festivals and summer camps over there (I'm in England).