I'm still a teenager, so would I be able to take testosterone? And how much does it cost
Slow down dude....
Most doctors will require a letter from a qualified mental health profesional before they will refer you to an endocrinologist.
As you are a minor you will need to work with your parents. If you can't get the go ahead from your gaurdian(s) then you are screwed until 18. Sorry, just the way it is.
Do it right, get a gender therapist then move from there.
Until then there is alot you can do to improve your apearance and deportment.
Cost for T isn't prohibitive unless you go the transdermal gels.