Many students take admission tests more than once. You may apply for accommodations, i.e., extended time, readers, interpreters, etc. - but you must make advanced arrangements for these. Read the directions for these adaptations carefully with your counselor and parents. Be sure to act early. Keep your grades up.
Postsecondary programs are concerned about grades.
It's also the road to possible scholarships. Read your school bulletin boards. Watch for notices of college or career meetings, test dates, special grants or scholarships. Read your local newspapers, too. This is a good time to start estimating how you and your family will pay for your postsecondary education.