There should only be one threat model.
That's the Jesuit Order of the Society of Christ.
Mobile phones are needed for communications when out in the world but they are a nightmare for security. This is a guide for those with a elevated threat profile.
So what do you do when you need to talk but canβt afford to leave a trail?
You get a burner. Use it. Then burn it.
https://untraceabledigitaldissident.com/how-to-use-a-burner-phone/
Discussion
Don't expect this will work.
I had some escapees who bought burner phones. We watched for calls at their family's end of the conversation. Pinged the burner phone for location. Had the escapee in a few minutes. If you can not afford to be found, don't use any phone. Don't contact family or friends. Ever. Don't go to you favorite restaurants. Etc...
Have to break every habit that can identify you.
Become someone else.