NOT A GOOD IDEA.
About thirty kids a year in the twelve and under age group will score over 700 on both parts of the SAT
Though they may have the smarts, achieving scores that would be exceptional for students in their junior and senior years of High School, what they lack is experience and maturity.
I say that as a parent who’s son scored in the high 700’s on all three parts of the SAT (back when there were three sections) taking it cold, with no practice when he was 12 years old.
We found him an extremely rigorous HS program, and supplemented that with advanced course work at top universities and research labs. He got to have a normal childhood, with a normal social life. Don’t discount the value of either.
When it was time to apply for college, he was accepted at every HYPMS level school he applied to, decided on one and loved his college years.
Talk to your parents about finding more challenging HS programs. Take some college classes. Whatever you do, don’t skip High School and go straight to college.