Apple added satellite messaging with the iPhone 14 series. So the iPhone 14, iPhone 15 and iPhone 16 all have this feature, and it is included for free. Google added satellite SOS on the Pixel 9 series this year.
There is a way to use it for emergencies.
And you can also use it to send and receive regular text messages. When you don’t have service, the satellite service will pop up and then you have to wait for it to find a satellite and then it will tell you how to turn your phone. What I found is that you have to keep turning your phone.
All the info in this article: How to Send Messages over Satellite on Google Pixel and iPhone