I’ve taken you through how the Magento 2 API works. This is where I send you off on your magical journey. There are lots of integration points that you can access with this API, and now you can write even more for yourself. The fundamentals are there, and you should get the gist of how things work.

Additional reading might help if you’re new to Magento, PHP, and APIs:

Magento’s Dev Docs
PHP.net
RESTful API Tutorial

Good luck on your adventure!

-Dan