How to test if my plugins works?

Hey everyone, I’m trying to do my own plugin, but I’m not really sure how to test it; I did follow the steps on mautic documentations, and as far as I understand I need this structure (at least)

HelloWorldBundle/

      • Config/
          • config.php
      • HelloWorldBundle.php

I even create a translation file, due to also create a Evenlistener file

What’s the right way to create and set up the config.php file to event listener?