Actually, we can apply the TEXT function to convert numbers (from 1 to 12) to normal month names easily in Excel. Please do as follows:

Select a blank cell next to the sales table, type the formula =TEXT(A2*29,"mmm") (Note: A2 is the first number of the Month list you will convert to month name), and then drag the AutoFill Handle down to other cells.

Now you will see the numbers (from 1 to 12) are converted to normal month names.

As you see, the TEXT function can return month name in another cell. But if you have Kutools for Excel installed, you can apply its Operation feature to replace the numbers (from 1 to 12) with month names directly.

1. Select the numbers you will convert to month names in the sales table, and click Kutools > More > Operation. See screenshot:

2. In the Operation Tools dialog box, please (1) click to highlight Custom in the Operation box; (2) type the formula =TEXT(?*29,"mmm") in the Custom box; (3) check the Create formulas option; and finally (4) click the Ok button. See screenshot:

Now you will see the month names replace the selected numbers directly. See screenshot:

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