Having an idea of the kind of career you would like to pursue makes it easier for you to prepare. If you are completely unsure of what you want to do, seek some career planning advice. There is nothing wrong with keeping your options open. It is better to postpone making a decision than committing yourself to just one possibility that you might later regret. It is not necessary to choose a major before you start college.
Students often change their majors while in school.
Don't be alarmed if you don't know what you want to do . You need to perform well in high school. Try for the highest grades you can achieve. This shows the admissions officer your abilities and helps you build strong study skills. Getting good grades is only one aspect of well-rounded preparation.