Yes, to use the OpenAI ChatGPT robot skill, you need to have a valid API key from OpenAI. You can obtain this key by creating an account on the OpenAI website. Once you have the API key, you can enter it into the configuration menu of the OpenAI ChatGPT skill in ARC.

Here are the steps to get the API key:

1. Visit the OpenAI website and select the API option from the menu.
2. Press the SIGNUP option to create an account.
3. Once the account is created, press your Username icon to view the drop-down. And select the View API Keys option.
4. Copy your API key.
5. Paste the API key in the robot skill configuration menu in ARC.

Please note that the cost associated with queries to the OpenAI API may apply, and it's quite low - and may only be a few dollars a month. If you have already done this and are still experiencing issues, please let me know so I can assist you further.

Also note that there is a step-by-step instruction manual for the Open AI ChatGPT robot skill here: https://synthiam.com/Support/Skills/Artificial-Intelligence/OpenAI-ChatGPT?id=21559