There’s not one answer that will cover all situations.
NPCs can work for international students, but it can be difficult for families to fill things out accurately and with proper currency exchange rates (which can fluctuate obviously, sometimes dramatically).
Some schools might do a financial aid pre-read, others won’t. All one can is ask.
I don’t have data, but I am under the impression that most international students who attend US colleges (who didn’t go to HS here) are full pay because most schools don’t come close to meeting full need for most applicants.
I expect many international students receive acceptances that they can’t afford, especially when layering in travel and health insurance costs, plus onerous visa requirements.