Hi @NndnG
Currently, if you click New > OneDrive - Personal > we are unable to change the 'OneDrive-Personal\Document' as the default location for new notebooks.
I suggest you submit the feedback to Microsoft Feedback Community.
https://feedbackportal.microsoft.com/feedback/forum/c06dcc30-2e1c-ec11-b6e7-0022481f8472
As a workaround, you may start OneDrive syncing on your machine, then go to OneNote > Options > Save & Backup > Save section > Default Notebook Location
, set one OneDrive folder as the path.
Then if you need to create new notebooks, please go to New > This PC > Enter the name, then the notebook will be created in the OneDrive folder you set.
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