it's also said he was really gifted, maybe he got a high IQ
there is a genius who graduated at the age of 13/14 if I remember well, and it's true it's hard for people to trust them whatever their speciality is, so he had to continue to study until he reached "the good age" to be trusted enough
I had a 15 year old graduate college with me.... so it’s totally possible. They usually don’t do traditional education, but special tutors and such. Then they take special opt out test and things like that. So it’s rare but very possible.
"20 years old. he was a gifted doctor when he was alive." ? idk how things work there but in my country studying medicine takes 6 years so it's an impossible task to be a doctor at 20. maybe not fully a doctor, barely could be an intern tho.