Suggested by Shaker Professor_Peacock: "What is something you do on a daily basis that you don't remember learning how to do?"
The first thing that comes to mind is reading. I started reading by age 3, so it predates most of my memories of anything, including learning how to read. I'm sure I went through the entire thing of learning the alphabet and how to sound out words and all of that, but I don't actually recall any of it.
What I do recall is being very bored in kindergarten when my classmates were being taught the very basics of reading, because I already knew them. Eventually my kindergarten teacher enlisted me (not because she needed my help, but because I was bored) to sit with kids who were having trouble and work with them on their letters.