Inserting a file isn't currently possible in Excel for the web. You can, however, insert a file in the Excel desktop app.
-
To open the desktop app, at the top of the ribbon, select Editing > Open in Desktop App.
Don't have the Excel desktop app? Try or buy Microsoft 365.
-
Choose where to insert the content of the file.
-
On the Insert tab, select
-
Select From File.
-
Choose the file to insert and select OK.
