Power Query to access SharePoint site list of files

Hi - I am learning to use Power Query.  I want to connect to our intranet SharePoint site and drill down a few directories to where the Excel files reside.

What is the correct syntax for the SharePoint URL that would take me down to the subdirectory where I can see a list of the Excel files available?  I set the URL to:  https://companyname.sharepoint.com/sites/CorporateQualityReports which it looks like it was OK but it seems to be caught in some kind of loop where it says "LINKS - creating relationships" for the last 30 minutes.  What is the proper way for Power Query to access SharePoint directories? - Gary