This article explains how to enable the Fill Down command using a keyboard shortcut or mouse key in Excel 2019, 2016, 2013, 2010, Excel Online, and Excel for Mac.
How to AutoFill Formulas in Excel Without Dragging | Using Keyboard Shortcuts
The key combination to apply the Feed Down command is Ctrl+D.
Follow these steps to learn how to use Fill in your own Excel spreadsheets:
Enter a number in a cell.