I had these blind spots as a 20some year old, so I assume I had them when I was 12-14 too:

• I assumed that if I was good at something, I would be good at it forever. Turns out skills atrophy over time. Surprise! (This seems similar to your Anki revelation.)

• I am agenty. I had no concept of the possibility that I might be able to cause* some meaningful effect outside my immediate circle of interaction.

* I did, of course, daydream about becoming rich and famous through no fault of my own; I wouldn't say I actually expected this to happen, but I thought it was more likely than becoming rich and famous under my own steam.