In this module you can learn what exponents are and how to work with them.
In this 10-minute video from Khan Academy, Sal Khan explains the basic concept and notation of exponents.
In this 6-minute video from Khan Academy, you can learn about negative exponents.
3 to the 2nd power is 3 x 3, or 9. It is NOT 3 x 2, or 6.
3 to the negative 2nd power is 1/(3 x 3), or 1/9. It is NOT -9.
Study and practice
Use these search terms to find your own resources:
working with exponents