For me, it was through reading books! Two books that have shaped my entrepreneurial journey are - Rich Dad, Poor Dad and Steve Jobs by Walter Isaacson. I read these when I was pretty young, and they inspired me to start something on my own!
I bought bracelets on alibaba and sold them on etsy with Instagram as my main marketing channel about 9 years ago.
Switched to a newsletter business because it's so much easier to scale.
Great Q!