So... I'd recommend college or trade school for several reasons.
One is that if you have a bachelor's degree in any field, you have a lot more job opportunities than if you don't. Even if it's not a job specifically related to your major, more things will open up to you. You could still be a nanny with or without a degree, but with a degree you could be something else too if you so choose.
You can grow an art career with or without an art degree. There are a ton of online resources and classes that are way cheaper than college. The difficult thing here is that you'll be working remotely and disciplining yourself. If that's not your thing, college might be better. You can always change your major later if it doesn't seem to be working for you or if you'd like to keep art as a side thing. Choosing to go to college doesn't mean you're locked in to only one path for the rest of your life- it gives you more options rather than less. It's okay to enroll in college and be "Undeclared" while you figure yourself out.
You'll meet great friends and colleagues that you will have a much harder time finding outside of college or the professional world. If you put yourself in a place where bright and creative people are, you're more likely to find that rubbing off on you. The friends you make in college can be friends for life, and the connections you make can create really solid networks for employment later on.
Finally- whatever you choose won't be wasted. You'll learn, grow, work hard, and gain proficiency in something valuable. Your experiences will shape you and you'll grow from them, whatever you choose. The most devastating thing you can do to your future self is be paralyzed by fear and fail to act. Make the best choice you can and move forward, knowing you can change course as needed.
(I'll admit my bias right here: I did get a degree in art, I am employed in artsy fields and I freelance, I'm doing pretty okay financially and getting paid to teach and create art. It can happen!)