Dear James,
Good day! Thank you for posting in Microsoft Community. We are happy to help you.
According to your description and screenshot, it seems that the list name you required to have in the flow, but you didn’t create any list in this site, please try to create a list in this site then to run the flow to check the process.
Besides, regarding your query on Power Automate flow. since our forum is focused on the question with office e365 products. Please understand that this query is outside of our support boundaries. For you to be assisted properly, please reach out to Power Automate community by visiting this Microsoft Power Automate Community - Power Platform Community. I am sure that our experts from that team can address your query effectively and accurately.
Meanwhile, we found some reference and hope it can give you some ideas:
Solved: Creating a Folder Structure based on Subject Line - Power Platform Community (microsoft.com)
Solved: Automatic creation of a structure in a new folder - Power Platform Community (microsoft.com)
MS Flow – Create new folder action - Power Platform Community (microsoft.com)
Thank you for your cooperation and understanding. Please do not hesitate to post your queries in Microsoft Community and we will always do our best to assist you!
Your understanding and patience will be highly appreciated. Hope you have a good day and keep safe!
Sincerely,
Stacey | Microsoft Community Moderator
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