imo, the thing I regret most about that period of my life was taking it seriously. I got the good grades and tried to please people, especially my parents. If I had realized it was all a joke and that it wouldn't amount to helping me in life later on, I would have gotten a GED or something and planned some options from that. Or if finishing high school, at least prioritized my time to something better.
What I'd tell my younger self, if I could. Take the prison time of school to learn real-world skills from various people. Learn how to do things so I wouldn't have to rely on other people so much. Learn business and investing, how to run a business, how to invest in real estate and even the stock market. And to not emotionally, mentally, or financially invest in politics, unless it's for my direct economic or political self-interest. There's too many distractions.
That would have helped me immensely.