Can you explain the American insurance / medical industry?

That is a very complex question. If you were born with a defect and your parents were insured, insurance may cover most of it and still leave your parents with a bill for a portion. If you were a child, it depends on if you had insurance from what ever source. If you were an adult you would be expected to either buy private insurance or go through the marketplace for some subsidizing (at present). You would still be responsible for a good bit of the bill. If you had no money or insurance you could apply for Medicaid and then the state would pay to help fix you if you found a facility that accepts Medicaid.

I imagine you're sorry your asked. :) There is really a lot more, but too much for a hypothetical question.