I would think that many mentors may not want to take on someone under 18, but you will probably find someone online that may help you, just be very careful. Perhaps join a Wicca site so that you can benefit from a more public setting, but then again most have an over 18 setting for a good reason. It might be safest to start from a book. Do you only have an interest in Candles? not wicca or pagan too? There are many books that cover this subject that would be a good place to start you off whilst you wait to turn 18
