If your parent is a lazy hack and teaches you nothing about the world you just entered I feel sorry for you. Other than that, You can learn all of the shit they teach you in school on the INTERNET and yes, even how to grammar, and spell, Brazilians and stuff do it all the time. They know not a lick of English, but they can read and type it slightly.
Skulfuk, it's not that Black and White. Just because you didn't go to school, or dropped out before you got to highschool, isn't going to make you instantly homeless, Your odds of being homeless just goes up. Your not homeless until, you're homeless, Every decision you make may lead there after you dropped out or something, but there is always that chance you can bounce back before you actually do go homeless. Hell, I've see a couple of homeless people pull themselves out of the trash and get jobs as janitors and what not.
Not every job requires Grade 12, Everyone can't aim for the stars, or who will there be left to use as stepping stones?