How can I enable GeoIP/GeoSite for a random country?

[Coderx7]

Hello everyone, hope you are doing great.
I was wondering how I can enable GeoIP/Geosite for Iran, where it doesn't use proxies for domestic websites.

I glanced at the settings, specifically, the V2RayN settings, but the Geo files related options are readonly and I couldnt set anything there!, There seems to section called Regional settings which has only Default and Russian as select-able options and I have no idea how to configure it for myself.
Can anyone kindly explain how I can achieve this ?

Thank you all in advance