curl --request GET \
  --url https://demo.onlinebillingform.com/api/v1/country/get \
  --header 'token: <token>'

{
  "success": true,
  "country": {
    "id": 1,
    "name": "Afghanistan",
    "iso2": "AF",
    "iso3": "AFG",
    "isoNUM": "",
    "address_format": "",
    "postcode_required": 0
  }
}