Let's quickly remind ourselves of the school definitions:
PHP is one of the most common programming languages that we use when creating websites. , PHP is an essential component of most of the web pages you visit every day.
PHP-FPM or PHP-CGI
Each has its own application, but for this article we will take as an example the installation of the FPM version for the entire domain, and within the domain we will install the second version of PHP CGI in only one working folder.
Let's say if you have two installations in the same directory and one of them works, God forbid, on version 5.6 of php like our state institutions in Croatia, for example.