When I was 12 years old, I bought my first computer with my paper route money from my friend's grandfather (who actually just passed away a couple weeks ago). It was a Tandy 1000 that was manufactured before the Windows operating system became standard on home computers; it was completely MS-DOS-based. On that computer, I discovered the Microsoft Basic computer programming language within MS-DOS and began creating programs using only the "Help" menu that would generically briefly describe what a command did. There was no internet or available syntax tutorials back then; it was all trial & error. In no time, I was creating my own "Mad Libs" and a "Yahtzee" game and all kinds of stuff.
When I was a senior in high school, the school had a new "Computer Math" class that an algebra teacher "taught". I took the class and wound up teaching the teacher more than the teacher taught me regarding actual coding. Needless to say, I thoroughly aced that class (despite getting a zero on our final big project and getting suspended from school for a week for splicing a "Put Her In The Buck" by 2 Live Crew snippet into the program as an Easter egg).
Fast forward, I (nearly) single-handedly created the software that runs my whole company. (My boss had created one form and some code for that form in a software that includes over 100 forms and has since been replaced by my form and code.)