Help with using Power Automate/Graph connector to write to 365 Profile

I have followed this excellent demo to configure a custom Power Automate connector and use Graph to create a new Group and Team:

Create a Microsoft Graph JSON Batch Custom Connector for Power Automate - Microsoft Graph | Microsoft Docs

However, the next step is more difficult. What I want to do is to use a Power Automate flow to write to any users' 365 profile to update projects and skills which I can then explore through Delve.  Presumably instead of granting privs to read/write to Groups, I need to grant privs to write to 'User' but could anyone help me out with the JSON code to do so or to point me at the DOM reference that defines the User profile data model?