What would a person taking prelaw as major become?

A person majoring in pre-law doesn't become a specific job title. "Pre-law" is not a major in itself, but rather a *program of study* designed to prepare students for law school. Someone with a pre-law focus typically chooses a different undergraduate major (like Political Science, History, English, Economics, or Philosophy) while taking courses recommended for aspiring law students.

After graduating with their undergraduate degree and successfully completing the Law School Admission Test (LSAT), they would then apply to and (hopefully) attend law school. Upon graduating from law school, they would then become a lawyer (also called an attorney or barrister). Even then, the type of lawyer they become depends on their specialization (e.g., corporate lawyer, criminal defense attorney, family law attorney, etc.).