Carpentry learned in a library! Wow, no wonder that people make ignorant "just pick yourself up by your bootstraps"-type comments. Complete and utter disconnection from reality.

Tell us, what are the things you could learn at a library that could translate into earning income?

I don't recall saying there was anything that you could learn in a library that would translate into earning income. Though if I were in a situation where that was my only option, I'd personally pick web programming. That probably has the lowest barrier to entry of anything you could actually learn by just reading a book.

Would you hire a carpenter who had 0 experience but had read a lot of books at the library when you could alternatively hire a carpenter with actual experience?

Is sewing still a viable source of income? There are a few shops where I live, but they all seem to be run by old people with immigrant background (no offense, it just might indicate that they are willing to work for little money).

Carpentry takes years to learn the official way where I live. And you need tools.