FF where do you think the doctors got educated? From studying in universities and getting formal education for an average of 8 years.
Definitely not learning online. If that was the case everybody can become a doctor.
I wonder if you have children. Would you be against sending your children to school?
I don't know which hospital you went to, but Doctors usually say, IF you are in a sexual relationship to use condoms and birth control pills for prevention and IF you have several partners to get tested once a year atleast.
It is called safe sex because you do the best to protect yourself.
There are no stupid questions, but there are a LOT of inquisitive idiots.