A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data
Unlike Word, Excel has never had a built-in option to change case.
You can use the UPPER, LOWER and PROPER functions to return the UPPER CASE, lower case or Proper Case version of text in another cell.
Or you could create a macro to change the case of text in a cell itself, and assign a keyboard shortcut to the macro.