You'll probably have to connect to the computer running MyNode via ssh and install the pool software there. If you have no idea how to do that, feel free to ask any questions, or to use an LLM.
IMO using chatbot/AI/LLM should be last resort, especially when you can't understand/verify the suggestion. Besides, myNode also have documentation on
https://mynodebtc.github.io/ that include how to access terminal and connect via SSH.