What can I do after 12

How about 13.

Not fair J9, you stole my line! :)

After the age of 12 you can go to the next grade, get good grades, and then continue your education until you graduate.

Your question is way too vague to answer.

A person, if they have the funding (Money) can do all levels school, elementary, middle, high school, university including Masters and PhD by distance learning.

12 what? Age, grade, what? If you expect us to help you you have to give some background info.