Bach's vast catalog of music is worth noting, as many musicians have gone on to study his works. Although it might sound silly, having so many children was impactful, as several went on to become successful composers. He also wrote the Well-tempered Clavier, a very important piano study. Most of those things can be found online if you want to investigate further.
Here is an article that can be accessed on Google Scholar that takes a look at how Bach actually taught music: Remeš, Derek (2019): New Sources and Old Methods. Reconstructing and Applying the Music.
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