Place the cursor at the bottom of the formula bar and you will see the twin sided white arrow. Press the Enter key to have a result. Type the letter N and in parentheses type your Comment in quotation marks.
Next click on Excel Options and move to the Advanced tab.
On the Home tab in the Cells group click the Format button and select Unprotect Sheet from the drop-down menu. On the Home tab in the Cells group click the Format button and select Unprotect Sheet from the drop-down menu. Scroll down to Display. Want To Use The Keyboard Shortcut To Resize The Formula Bar.