The tutor is about how to use Enable PHP for Websites via ISPConfig.
Debian 9.x 64-bit
Test mail domain: mssqlhost.com
1 Login to ISPConfig control panel.
2 Click "Sites" tab and then click "Add new website” to create a new website.
3 Choose the website IP and type the domain.
4 Enable PHP for this website.
5 Check the website that you just created.
6 Check the PHP information via phpinfo.php.