I learned what I was interested in shooting...by shooting, and being satisfied or dissatisfied with the results over time.
And you were never influenced in what was satisfactory by any image you didn't make??? I would expect you had long before learned what you like, and by shooting and shooting you learned how to produce it.
I knew by the time I was ten years old what kind of images most interested me, and that of course could happen only because like everyone else I had been exposed to photographs from the time I was able to focus my eyes! Virtually every child will see thousands and thousands of photgraphic images by the time they are out of primary school.
By the time we are teenagers, if pictures interest us, we have already formed some mental concept of what is "nice" and therefore of what we might later decide to make ourselves.
The idea that anyone actually experiments with every possible style and develops their interests soley based on their own work is attrociously narrow.