Here is a step-by-step guide on how to add new items: Select the cell with the drop-down list: Click on the cell where you have the drop-down list. Go to the "Data" tab: In the Excel ribbon, navigate to the "Data" tab. Click on "Data Validation": In the "Data Tools" group, you will find "Data Validation." Click on it.
Create a drop-down list In a new worksheet, type the entries you want to appear in your drop-down list. Select the cell in the worksheet where you want the drop-down list. Go to the Data tab on the Ribbon, and then Data Validation. On the Settings tab, in the Allow box, select List.
Fill formulas into adjacent cells Select Home > Fill, and choose either Down, Right, Up, or Left. Keyboard shortcut: You can also press Ctrl+D to fill the formula down in a column, or Ctrl+R to fill the formula to the right in a row.
Select the cell in the worksheet where you want the drop-down list. Go to the Data tab on the Ribbon, then select Data Validation. On the Settings tab, in the Allow box, select List. If it's OK for people to leave the cell empty, check the Ignore blank box.
On the worksheet where you applied the drop-down list, select a cell that has the drop-down list. Go to Data > Data Validation. On the Settings tab, click in the Source box, and then change your list items as needed. Each item should be separated by a comma, with no spaces in between like this: Yes,No,Maybe.