The round things worn on the arm and abdoment are the sensors and you wear them for up to 15 days. There is no separate device - the sensors send the result to your smartphone. That’s why the Facebook poster is asking for any one of three types of sensors.
But here’s a couple of things that most non-diabetics wouldn’t necessarily know. First , CGMs are generally only prescribed for insulin-dependent diabetics. And second, lots of people who are not insulin-dependent diabetics want them - enough so that there are OTC version in the US. I’m not sure what the difference is.But it’s possible that the person’s issue is that it’s not considered medically necessary for her.