It is possible to have Excel for iPhone or iPad read aloud a workbook. The options aren’t very good but we’ll explain what’s possible.
We have to turn to the iOS Accessibility options at Settings | Accessibility | Spoken Word
Turn on Speak Selection.
Optionally adjust the Speaking Rate and choose from the Voices available.
In Excel, a Speak option appears in the popup menu for a selection.
That’s the good news, now the bad news.
Speak will only read one cell. Even if there’s a many cell selection.
Speak Screen in Accessibility might seem like an alternative but, unfortunately, it only reads the menus and tabs, not the worksheet.
Microsoft should fix the Read Aloud options in Excel 365 for iOS. Either change the Speak option so an entire selection is spoken, not a single cell. Or add the Read Aloud option already in Word for iOS and Excel for Windows.
Read Aloud a doc in Word for iPhone or iPad
Read Aloud in Word 365 and 2019 in depth
Unhelpful Office error message for Read Aloud
Powerpoint speaks aloud in Office 365, 2019, 2016 and earlier
Excel speaks aloud cells
Hear a document with Speak in Word 2016, 2013 and 2010