Can I track AFib on Apple Watch Series 10 without an iPhone?

I just bought an apple watch series 10 with cellular for my father-in-law. The main purpose of buying the watch was to monitor his heart health, particularly AFib. None of us in the family have an iPhone and I didn't know that the watch can only be used with an iPhone, not standalone. I have used fitbit and other devices that can be used standalone or paired with any phone using bluetooth. I really don't need the watch to make calls or send texts and I can't afford to buy an iPhone since I just bought new mobile phones. Could someone pls suggest how I can still use the watch for the purpose mentioned above.