A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data.
Above the Ribbon Menu should be a search box, type touch in that search box, you should see a setting to switch between Mouse and Touch input, ensure that is set to mouse, that should reduce the size of the text and icons in the top menu.
If that does not resolve the problem, that is usually the only setting available, please provide a screenshot of the Excel window so I can see the problem you are experiencing.