It’s hard to pick just one.
I watch a few channels related to atheism/skepticism and/or philosophy like Genetically Modified Skeptic, Telltale, and Alex O'Connor among others.
I watch some channels about the piano such as Heart of the Keys and Tiffany Poon.
Same question.
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"Les grandes personnes ne comprennent jamias rien toutes seules, et c'est fatigant, pour les enfants, de toujours et toujours leur donner des explications." - Le Petit Prince