I want to create secondary directory on sharepoint site contents list, but not have this function

Terry_Jin In SharePoint, you cannot create nested library/lists. However, you can create multiple libraries or lists in a SharePoint site and then you can create folders inside libraries/lists.

If you want to connect two lists/libraries, you can use lookup columns in SharePoint. Check below documentations for more information:

1. Create a document library in SharePoint 
2. Create a folder in a document library 
3. Create list relationships by using lookup columns 

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