I Watch 10 bought in New York

I bought the Apple Watch 10 in New York not knowing that the oxygen level measurement didn’t work in the USA, I should have bought it in Luxembourg for the same price and it would have worked. It was just fun on holiday to so see and buy at the big Apple shop. What can be done to make se oxygen level to work. I ware my old D2air Garmin watch for the moment as it works on that one