Can someone please explain what “premed” is?
Premed commonly refers to a path students interested in applying for medical schools take. It is not a major at most of the schools in the US. Academically, it involves completing the pre-med coursework at college, which are two years of chemistry, with one being in organic chemistry, one year of biology, and one year of physics. English and Calculus courses maybe required depending on the policies of the medical school one wishes to apply for.
Some of the popular pre-med majors are biology, chemistry, neuroscience, psychology, and other STEM courses. However, a student on a pre-med track is permitted to choose any undergraduate major as long as the course requirements are completed; I have seen an Economics major pursuing pre-med track and eventually get into a very prestigious medical school.