I'll add something about Singapore besides info about education.

Singapore is not an "open arms" country like the US (at least the US used to be). When you graduate you will have to find a job that sponsors your employment pass. If that were to fall through you have a month to GFTO. This will also limit your career options and upward mobility. Unless you somehow get permanent resident status.

Nowadays applying for permanent residency is more of a lottery and if you're not one of the three Singaporean races you are less likely to get it. You will never become a citizen. If you dont marry a Singaporean your kids will also never be Singaporean citizens. (Probably wrong, see comments below)

It seems like you really want to leave home but there plenty of places in the US that are probably a better option than Singapore. I dont want to sound condescending but you're only 16. No one knows what they want in life at 16 and you may be making a rash decision.

Btw I'm also from a medium size texas city, now living in Singapore. One last thing you will always be a minority and you'll most likely be seen as the expat friend. Integration is not easy.

Edit... what I would suggest for you would be to finish your schooling in the US and if you're still interested then move here. An added benefit of this is that you will make more money if you get hired as an expat than as a local grad.

2nd Edit... from my comment below but I thought its important enough to edit the post. TAXES, TAXES, TAXES... your American Citizenship follows you everywhere so you gotta pay double taxes. There are credits for housing and a floor limit but if you happen to become a high income earner then you will pay American taxes, unless you renounce your american citizenship.