1. Go to this page and download the library: Download ikkez/f3-opauth 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/ */
ikkez / f3-opauth example snippets
// adjust the autoloader
$f3->set('AUTOLOAD','lib/opauth/');