In some rare instances the courts have allowed a minor to become “Emancipated”–to assume their own responsibility for their own care and to severe the obligation for such care with the parent(s). In order for a court to allow such a legal severance of the parental duties, a petition must be file before a court of competent jurisdiction (usually a Juvenile or a Probate & Family court) where a hearing or series of hearings will be held.
In order to qualify for a legal emancipation you must: (a) be married, or (b) you must be in the U.S. armed forces, or (c) you must be living apart from your parents or guardian and be managing your own money and attending school regularly, or (d) the court must decide that emancipation is in your best interests, or your parents, or your minor child (if you have any).
You should consult with a lawyer specializing in juvenile law. The juvenile court or probate court may appoint one for you at no charge.
Here is a link to a website that gives you a summary review of the process.