In my youth, Hastings and Musicland sold piano sheet music in the back. I did the old "decode and memorize" trick with Billy Joel's "Piano Man" and Elton John's "Candle in the Wind".
Both have been lost to time now.
Frankly, when I started playing guitar, something called the "Online Guitar Archive" (OLGA) was accessible. It contained user transcribed TABlature files for just about every song out there. I'd locate one that I thought I could accomplish, figure out how to play, reset, play, reset, etc the fingers.
Of course, western music is really repetitive, so over time, the fingers learned to make the chords without thinking. Similarly, the single note runs come in a few flavors and only vary by where you start on the neck.
My brain learned to control the individual fingers on the left hand 15 years earlier when I picked up the cello, so I had a head start on that part.
