Required in PHP

Question

I’m a beginner in PHP and I’m trying to import a plugin to my page, but I don’t know how to call it, I’m currently using the phpspreadsheet and I care about him this way:

  require $_SERVER['DOCUMENT_ROOT'] ."/creating/assets/plugins/phpspreadsheet/vendor/autoload.php";

Now I’m trying to use Redis, for a cache system, but I don’t know which file in his folder to call, there’s no autoload.php like the phpspreadsheet the structure of the folder is as follows::

I’m trying something like:

 require $_SERVER['DOCUMENT_ROOT'] . "/creating/assets/plugins/cache-master/Simple/";