What high school courses and college paths should I be focusing on?

Hello everyone! I am currently an 8th-grade student preparing to enter 9th grade, and my long-term career goal is to become a dermatologist. Since I am about to start high school, I want to make sure I am setting myself up for success early.
I would love to get your advice on a few things:

High School Courses: Which AP, IB, or advanced science and math classes should I prioritize over the next four years?

College & Pre-Med: What should I look for in a university or undergraduate program to best prepare me for medical school? Are there specific majors you recommend?

Extracurriculars & Tips: What can I do outside of the classroom (like volunteering, shadowing, or clubs) to build a strong background?

Thank you so much for your time and guidance!