As my example makes clear, you can remove the ribbon completely
To answer your question directly, you cannot remove the backstage (File menu) if you need to have a ribbon
However, you can completely remove all the contents of the File menu leaving an empty backstage.
Here's a very exciting screenshot of that:
View attachment 110131
For details of how that is done, see my article:
This article explains how to apply various security measures to make your databases as secure as possible. An example app is used to illustrate the possible methods available
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