I didn’t realize that you were in Kenya.
Here is what I would do. Make sure you have a valid passport and enough money for a one-way plane ticket.
Apply to colleges that meet full financial need, and check with them beforehand if you will be required to submit information for the non-custodial parent. If you are, then skip them. That UChicago suggestion earlier was very helpful. That’s the kind of thing you are looking for. Also apply for merit scholarships, but that full ride is becoming very hard to come by.
Be prepared, that all of this might fail. You may not be admitted to an appropriate college that you can afford.
You are however a US Citizen, and that’s valuable. Life is long. When you are 18 come to the US, to a city with a healthy economy. Get a full-time job and build a life.
I live in the Boston area, and the Harvard Extension school provides a high quality education at a very affordable price.
It’s designed for working professionals.
The economy here is terrific. We have universal healthcare. Housing is expensive, but young people around here all live with roommates.
https://boston.craigslist.org/search/jjj?query=entry+level
If you came to Boston, got a day job, and followed the procedure to matriculate, you would be able to slowly progress toward your degree, maybe taking 6 years. You’d have the degree by the time you are 24. It’s not an easy road, but someone of your intelligence can likely make a go of it.
You could also consider joining the military if you are so inclined, and go to college later. Colleges love veterans because they are mature.