Michael
Consent to treatment is vital to give anyone any form of medical treatment or intervention and there are rules and laws about it. You can read all about it here. You can ‘force’ teenagers and even older children to have treatment only if they lack capacity or if the treatment is life saving in which case even decisions by parents can be overruled. As the balance of benefit to children from the vaccines is not yet clear, and as there may be serious, if rather rare complications, forcing children to have vaccines would be utterly unethical and illegal.