Hi.
Open a text editor, paste the entire code into it and save it as, for example, repairCMS.php.
Upload the file repairCMS.php to FTP to the main folder where you have Prestashop installed.
Then enter a link to the file in the URL of your eshop, something like https://mysite.com/repairCMS.php
Then you can check in the database if there are records.