McKenzie, this is a smart thing to be asking while you are still in high school. Be sure your guidance counselor knows that you want to be a doctor so that you are taking the highest level science and math classes which are available in your school. Taking AP and honors classes, if at all possible, is great and I'm glad to hear you are doing that. You want to be as prepared as possible for the pre-med classes you will need to take in college in order to go to medical school.
Classes such as biology, chemistry, physics, earth science, mathematics. Overall make sure your curriculum is challenging as medical school is long hours and demanding. Take a few to several AP classes. You need to be getting used to long hours and lots of studying for medical school and medical internships.