It’s not super difficult to pick a college, but of course, one still needs to get admitted, so have back up plans. Make sure they’re affordable because you don’t want a lot of debt. Med school is super expensive.
It’s incredibly difficult to pick a med school since admission rates for all of them are super low. A quick google search shows me their acceptance rate is between 1 and 3% just looking at the search page.
Don’t get your heart set on “a” med school. If you’re like most people, you’ll be applying to many and praying for an acceptance.
Pick a major you like because you’re likely to do better in it. Many students pick something that can work toward their Plan B if they don’t make it into med school (roughly 57% don’t as of the latest stats).
Applicant/Acceptance GPA/MCAT data here:
https://www.aamc.org/media/6091/download?attachment
Get as good of a foundation as you can in high school, then work hard, get multiple hours of shadowing/volunteering, and be an “interesting” candidate during your college years.
Scroll through a couple of these to see what one med school looks for in successful candidates - then be someone your school can write about. (You can google more if you want to, but you’ll see it’s a template - they tend to look for the same thing year in and year out.)
You’re smart to be looking ahead and planning ahead. My son decided he wanted to be a doctor when he was 8 years old and never shifted off of it. Now he’s in his first year of residency loving it, even with the hours, Covid deniers, and other issues. If this is something you want, go in eyes wide open and prepare to work hard for many years. My son tells me it’s not work when you love what you’re doing. He loved his college and med school years.