1) Where are you? Fill out your profile completely so people in your area can assist you ranther than people on the other side of the country who may not have the same requirements.
2) Maturity has nothing to do with it. It's a matter of legal liability. You can not be held legally liable for your actions outside of criminal matters. You can not legally sign a contract until you are 18, therefore you can not legally sign a waiver. Your parent(s) or legal guardian can, but it depends on if your local group is set up for minors.
ASC Age Verifier for Red Deer & Area Alberta