How to get a certain flagged FIDE ID?

I'm not sure if I've phrased the title correctly using the word "flagged", but what I mean is, certain FIDE chess players have a flag on their FIDE profile, and some just have "FIDE". How do you get a certain flagged FIDE ID, and does it have to do with your birth-place, where you live, where you play chess, your heritage?

I may have gotten all of this completely wrong and this entire thing may make no sense, but I hope I can get my question across.

Thanks in advance.

In general, you have to have the flag of your associated national federation. In some instances, a player can petition FIDE to not play under that flag, without changing their associated federation.

https://fide.com/news/1618

https://www.fide.com/news/2119

It depends on your federation.

For example, I live in the US and am a US citizen. US Chess of the national federation and a member of FIDE.

If I play a dual rated event, one that is both US Chess and FIDE rated, I'll get a FIDE ID number (FIN) and my flag will be the US flag. I could also travel and play in a FIDE only tournament instead, but would need to contact US Chess in advance to get assigned a FIN if I didn't already have one.

Other countries have different requirements and some may not hold anything other than FIDE events, but it's up to them to handle the registration of FIDE IDs for their associated players.

Another option is to play on the official FIDE Online Arena, but I don't know much about that.

Assuming your flag is correct and you're a Polish citizen, you would work through http://www.pzszach.pl/