Legally, the only way to become a doctor (ie. practitioner) is to attend medical school.

However, you can also be titled “doctor” by taking a doctorate level course. You can then technically also refer to yourself as a doctor, if you want.

The final way is to append doctor to your name. You won’t really be a doctor (so this is little better than having people simply nickname you “Doctor Jim”) but you’ll be able to put it on official documents.

So, in theory, if your original name was Jesse Larkin you could rename yourself and push your first name to a middle name. Therefore, your full name would be Dr Jesse Larkin, with “Dr” being your first name.

As far as I know though, this is considered borderline illegal in most countries; you should talk to a legal professional in your area for assistance.

Study under a VooDoo doctor until he dies. Then assume the title and position of chief voodoo doctor.