i think you mean emancipation. you can get it if you can prove to a court of law that your parent(s) are unfit and that you would be better suited alone. it is usually quite difficult to become an emancipated minor unless there is reasonable cause for said emancipation. check with your local state laws about what age you must be, though i think it is about 16 for pretty much every state, (or at least somewhere around there.) good luck!
To relieve constipation, you can try increasing your fiber intake through fruits, vegetables, and whole grains. Drinking plenty of water and staying physically active can also help. Over-the-counter medications like stool softeners or laxatives may be used as a last resort under the guidance of a healthcare provider.