The bot logs in as user foo
To make foo join other channels, devise a way to communicate to the bot whislt it’s running
And tell the bot to JOIN #channelname
Just like any other IRC bot.
So here you may be logging in another broadcaster, to get “permission” to join their chat, but you don’t login to chat as the broadcaster, you are already connected as your bot, so you just need to be able to tell your running instance of the bot to join multiple channels without restart.
So devise a way to give instructions to the bot/script