curl --request GET \
  --url https://demo.onlinebillingform.com/api/v2/country/lists \
  --header 'Authorization: Bearer <token>'

import requests

url = "https://demo.onlinebillingform.com/api/v2/country/lists"

headers = {"Authorization": "Bearer <token>"}

response = requests.get(url, headers=headers)

print(response.text)

const options = {method: 'GET', headers: {Authorization: 'Bearer <token>'}};

fetch('https://demo.onlinebillingform.com/api/v2/country/lists', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://demo.onlinebillingform.com/api/v2/country/lists",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "GET",
  CURLOPT_HTTPHEADER => [
    "Authorization: Bearer <token>"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

package main

import (
	"fmt"
	"net/http"
	"io"
)

func main() {

	url := "https://demo.onlinebillingform.com/api/v2/country/lists"

	req, _ := http.NewRequest("GET", url, nil)

	req.Header.Add("Authorization", "Bearer <token>")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

HttpResponse<String> response = Unirest.get("https://demo.onlinebillingform.com/api/v2/country/lists")
  .header("Authorization", "Bearer <token>")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://demo.onlinebillingform.com/api/v2/country/lists")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Get.new(url)
request["Authorization"] = 'Bearer <token>'

response = http.request(request)
puts response.read_body

{
  "success": true,
  "countries": {
    "current_page": 1,
    "data": [
      {
        "id": 1,
        "name": "Afghanistan",
        "iso2": "AF",
        "iso3": "AFG",
        "postcode_required": 0
      }
    ],
    "last_page": 17,
    "per_page": 15,
    "total": 253
  }
}

{
  "success": false,
  "errors": "Invalid API Key"
}

{
  "success": false,
  "errors": "Insufficient permissions for this endpoint."
}

{
  "success": false,
  "errors": {
    "id": [
      "The id field is required."
    ]
  }
}