I want to use pure firebase/php-jwt library in my code. Firstly, I go to /var/www/html/ and like the official library page is suggesting, I do this
As per the documentation, you need to include the autoloader.
E.g., in your php file:
require __DIR__ . '/vendor/autoload.php';
But... typically your vendor folder would be at the same level than your html folder (the one where you are serving content).
E.g.:
- Project root
--- vendor
--- html
----- index.php
Then in your index.php you'd do:
require __DIR__ . '../vendor/autoload.php';
It is nice that you trying to use composer and modules, but if I were you I'd try to read on a bit about php's autoloading features, so you understand what's going on, and how you can profit from them.