How to install PHP 5.6 and 7.0 - 8.2 with PHP-FPM and FastCGI mode for ISPConfig 3.2 with apt on Ubuntu 18.04 - 22.04

When using ISPConfig, by default, you only have the main PHP version for your distribution. This guide will take you through installing additional PHP versions (5.6, 7.0, 7.1, 7.2, 7.3, 7.4, 8.1, and 8.2) on a Ubuntu server with ISPConfig.