You can use the existing clientID/secret to generate tokens for your chat bot.
The guide assumes you don’t have an existing application. Since that guide uses an external token generator for “quick start”
I used to use a PHP library called “smartIRC” which needed some minor changes to make it ircV3 compatible.
But with your data being in a database you can call that database from any language.
PHP can be a bit fiddly with long running sockets. And I’m not sure what stuff exists in the IRC space since I’ve moved on from PHP for chat bots myself.