1. Go to this page and download the library: Download ptchr/magento2-rest-client library. Choose the download type require.
2. Extract the ZIP file and open the index.php.
3. Add this code to the index.php.
<?php
require_once('vendor/autoload.php');
/* Start to develop here. Best regards https://php-download.com/ */
ptchr / magento2-rest-client example snippets
php
$client = new Ptchr\Magento2RestClient\Client('BASE_URL', 'ADMIN_USERNAME', 'ADMIN_PASSWORD');