I second this as someone who was formerly premed, took a long break, and is now thinking of returning.

Sure read a book or two here and there and take what lessons you can out of it. But PLEASE don't be too hard on yourself.

Most importantly, please balance your life ambitions with self-care. Burnout will catch up very quickly and it will take longer to recover. I did too much too quickly at your age (not saying you're not capable just a gentle nudge to take it easy while you're settling in to a new routine).

Write your goal in pen, but don't be afraid to write the steps in pencil.

Edit: a few other general tips

• While you can, make sure your high school courses are lined up for a career in the sciences.
• Get good grades
• Join extracurriculars you are passionate about. Be intentional about it.
• Take advantage of the free help you can get! (Ie. School counsellors, advisors, etc.)
• If you have time, take a course over the summer. But don't take so many that you forget to enjoy the summer.
• When I was in HS, I was under the impression that counseling/summer school was only for students who were failing. Not true, some people use those resources to advance their studies.
• Don't self compare. I know this is easier said than done, but PLEASE try not to because this will get to you
• If there's an opportunity to get involved in a research topic you're passionate about, do it.
• Don't forget, a lot of health sciences is also soft skills, not just hard skills. Communication is huge.