So you're thinking of holmschooling
If you teach yourself how to be a full stack developer using Treehouse or Lynda while you're a high schooler, you could possibly find a job at 18 instead of going $60,000 in debt going to university for four years. With no debt, you could work at max out your 401k and IRA for $25,000 a year ($19k per year limit in your 401k, $6k per year limit for your traditional IRA at Vanguard) and invest in index funds (S&P500 index fund or Total Stock Market index fund) from age 18-22. Having $100,000 in retirement at age 22 ($25k * 4) would compound over 38 years (assuming 8% interest) to be worth $1,862,527 by the age of 60. That's the opportunity cost of college if you taught yourself to program in high school instead of college. Assuming a 4% withdrawal rate of your retirement account at age 60, just working as a programmer from age 18-22 and maxing out your 401k and IRA would permit for a $74,501 a year salary when you retire ($1862527 * .04). That's a healthy retirement, in my opinion. Obviously you have to account for inflation, but that's not bad for just four years of work. That's the magic of compound interest multiplied by long lengths of time invested in index funds. You could even, I daresay, work longer and sock more money into retirement, or start saving in a post-tax account (also invested in index funds at Vanguard) and accumulate enough to cover your expenses per year to become financially independent and retire early if you live frugally and save more than 50% of your take-home pay. Even if you go to college, maxing out your 401k and IRA from age 22-32 is another great way to ensure a comfortable retirement: $250,000 (10 years * $25k) compounding at 8% for 28 years (age 32-60) is $3,374,382 at age 60. That's probably more than you need, which means you can switch to focusing on saving for a post-tax account so that you can fund an early retirement until you hit 60 and can withdrawal from your 401k/IRA. Having an above-50% savings rate is easy if you live frugally and don't have college debt.
Open Educational Resources are books that have an open source license. That means that you can read them free online. Because computer scientists basically invented open source, computer science books are frequently open sourced. That's a good thing, it means there are ample opportunities to learn and study computer science for free online. Know what type of open educational resources are out there to discover is a good way to ensure that there are no limitations to your quest for knowledge. Money is less of a hindrance. By relying on open education instead of having to purchase expensive textbooks, you'll save money while still learning the material just as well as with a paid book. Many computer scientists are happy to open source their books in the hope that it fuels an education for people without income, so as a K-12 student, studying open educational resources for a little while so that you can find them online through google is a good way to protect your ability to learn computer science for the foreseeable future.
Now that we're aware of the benefits of a computer science job, let's start the journey of learning how to program!
TypeScript as a segue into Java
Now we're cooking with gas!
At this point you're reading college level beginning programming textbooks. You can probably move on to a common college curriculum, starting at the very beginning and reading some more complicated OER texts on Python/JS/Java to get a more thorough hold on them. Each of those three languages can be used for backend programming languages for web development (Django/Flask, Node.js, and Spring).