syuhada First step is to verify do you have PHP installed? If you can SSH onto the server (or command prompt if it's Windows), type the following:
php --version
If it returns an error saying the command php isn't found, then there's your problem! If it's a Linux box, usually just typing one of the following will sort it:
sudo apt install php
(for Ubuntu and other apt based systems)
sudo dnf install php
(for Fedora and any Redhat based system)
For Windows, go to php.net and download the 7.3 installer (not 7.4).