1.Select Cell: Firstly, open your excel sheet and click the cell you wish to add the drop-down box with the left mouse button.
2.Open the Data Validation dialog box:
Find and tap on the "Data" option on the menu bar.
Find and click on the "Data Validation" option in the drop-down menu, which will open the "Data Validation" dialog box.
3.Set up validation rules:
In the Data Validation dialog box, you'll see three tabs: Settings, Input Message, and Error Warning. Please click on the "Settings" tab.
In the "Settings" tab, you'll see a drop-down menu called "Allow". Click on this drop-down menu and select "List" from the drop-down list.
4.Enter the drop-down list item:
In the Source box, you need to enter the options you want to appear in the drop-down box. Note that each option needs to be separated by a comma. For example, if you want "Apple", "Banana", and "Orange" to appear in the drop-down box, then you should enter "Apple, Banana, Orange" in the Source box.
5.Complete the setup:
Once you have confirmed that you have entered all the options correctly, click the "OK" button to close the "Data Validation" dialog box.
Now you can go back to your excel sheet and you will find a drop-down box has been added to the selected cell. When you click on this cell, you can see all the options you just entered.