What major should for my undergrad degree to have the most success in getting into med school.

[nrtlax33]

Read https://www.usnews.com/education/blogs/medical-school-admissions-doctor/2013/09/11/choose-the-right-undergraduate-major-for-medical-school

I found the following statements quite useful

your major does matter on a personal level. As a premed, you need to balance three main factors when choosing a major: difficulty of classes, level of interest and convenience.
…
When choosing a major, remember that there is no one right choice for everyone. I believe my major made me the strongest applicant I could have been. Another applicant may need to be a humanities major in order to reach his or her potential.

In the end, the right major for you truly depends on the balance of what you are passionate about, what you can intellectually handle and what is practical.