I am 16 years old I used to live in USA
My parents took me to the us when I was very small I do not know much about mexico. Id really like to go back to usa legally finish school, my dream is to graduate with my friends and go to college actually be someone in life also when my mom and I crossed the border we got caught about 21 times so I don't think my mom or I can be eligible for a visa, while I was there I tried to do my best my record is clean ,what can I do?

You cannot do anything until you are of legal age. At that time you can apply for a visa. Your only chance at this point is to have a sponsor in the US.

Did you mother ever try to enter legally? I don't understand that she got stopped 21 times IF you lived and attended school in the US.