Hi! To be a ski or snowboard instructor you need a intermediate or better level to be able to go for the test qualified. Depending of which country you from the certfication are different but similar. Check at
www.snowpro.com for Canada and
www.psia.org for USA. Don'T expect to teach the highest level on your first season cause you will be disapointed. You will have to start had the bottom like everybody which mean beginner and youngster which is good to take experience.
Want more info you can ask me or one of the instructor from
www.skiproconnect.com maybe you can find an instructor from your mountain who can help you and give you the info where and how to pass your course.
Good luck