1. Go to this page and download the library: Download reyesoft/mercadopago 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/ */
$pos = new MercadoPagoPos('your_pos_external_id');
$qr_content = $pos->getQrContent();
// just an example, this is Endroid\QrCode library
$qr_code = new QrCode($qr_content);
$qr_code->setText($qr_content);
echo $qr_code->getDataUri();