This is my experience.
My wife and I are 70 and in the US. Both of us are US citizens with US passports, and I also have Italian citizenship with a passport, but have never requested an Italian health card because I want to be able to choose my hospital if possible.
Most US health insurance companies do NOT cover you outside of the US, except possibly in Canada.
We have purchased health insurance online for traveling overseas, but have not had to use it. We have found the prices to be less than most US health insurance. We have purchased plans with no deductible, with high benefit limits due to our age.
We are Covid vaccinated and that might possibly become a requirement or an option that requires an additional fee.
A few years ago we paid less than $300 total for both of us for a 3 weeks trip, so less than $40 per person per week.
In 2020, I was to be on the Camino for 3 weeks starting March 01, then meet my wife in France in late March for 3 weeks. Longest vacation ever celebrating retirement and 48 years of marriage.
Since I was still trying to convince her to go Caminoing with us, I bought the same 6 weeks plan for both of us and it totalled $700 with no deductible.
Well, I departed an on March 11 she contacted me and informed me that covid was getting out of control and flights were to be suspended.
My Camino friends and I headed back to Paris and returned to the US. My wife never left home.
When I arrived home, I called the insurance company, explained the situation, and respectfully requested a partial refund for her.
Well, lucky us, a few days later, the insurance company refunded every penny we paid for both of our premiums. (Not anywhere near as lucky with the river cruise company or airlines.)
Depending on the country, you might be asked to pay your bill before treatment, though the charges are more reasonable. This is much like in the US where someone might be asked to pay some of the inflated emergency room and hospital charges.
The company we have used in the past was GeoBlue.
Full disclosure: I have no relationship to GeoBlue except as a customer, and am a retired medical professional.
IMHO, when traveling out of country, the mantra "don't leave home without it" applies to travel health insurance.
Good luck.