EchoBot ChatGPT
Go to the ChatGPT.cs script and modify the apiKey const to your Open AI api key.
Feel free to navigate to the 'Context' method which contains how your AI will act, it already comes with prebuilt instructions which are easily changable.
The built-in Chat script utilizes inherits from the Event class, which subscribes to the MessageReceived event which makes it so that when the bot gets pinged/mentioned, it will initiate ChatGPT response, or if the bot gets a reply, it will also initiate a ChatGPT response.
Then you should be good to go