Hi @IT FA ,
What version number of Office did you use?
As the thread's comment it is resolved in 16.12 update:
https://excel.uservoice.com/forums/304933-excel-for-mac/suggestions/15694884-default-to-my-mac-instead-of-onedrive?page=5&per_page=20
I also suggest you refer to these links about default location in Office for Mac:
https://answers.microsoft.com/en-us/msoffice/forum/all/default-save-as-location-in-microsoft-office-on-a/41cb1b4f-95f2-44f3-8947-71b91dcab859?page=5
https://answers.microsoft.com/en-us/msoffice/forum/all/office-for-mac-2019-default-save-as-location/57734354-3231-4473-ad9b-677bd6f0f64b?auth=1
I also tested in both Office for Windows and Mac, I can find the option "Save to Computer default" in Office for Windows, but it's not existed in Office for Mac:
Refer to the links above and just checking in to see if the information was helpful. Please let us know if you would like further assistance.
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