If you don't want users to.
How to add drop down list in excel video. Apply data validation to cells. Then, customize the list using the data validation options. Web select a cell in which you want the dropdown to appear (d3 in our case).
In the data validation dialog. On the data tab, in the data tools group, click data validation. The data validation window will appear.
Select the data tools group from the data tab. In the source box, either update. On the first sheet, select cell b1.
Lock or unlock specific areas of a.