Medical card in PA

I'm turning 18 in a little over 2 weeks and have been interested in getting my med card for some time now.
I have ADHD, insomnia, anxiety, and depression, diagnosed by a therapist. Would I be eligible to get one? What websites would you guys recommend I use to get one? Should I apply on my 18th birthday or just wait? I don't know if I have medical documents for my diagnoses, if that matters.