you own the game rights and you can make agreements with your parents. Your parents would be responsible for other things like contracts or their own taxes. DO be aware the advantage of filling your own taxes vs not filling taxes. your parents are the ones who will sign the publisher agreement not you because of certain laws or publisher rule.
How is this done is mostly through the tax filling and agreeing that your parents did give you the right to make itch.io publisher account. Then you can upload your game and people will play it.