If you take college courses while in high school, those courses and grades (along with other college courses) must be reported on the medical school application.
If you take AP tests and score high enough for your college to give credit for them, be aware of the implications of such regarding medical school applications: FAQ Pre-med courses, AP/IB/etc. credit and college/DE courses, etc.
The main barrier you face in getting into medical school in the US is being an international student.