How to Use F8 Key For Advanced Boot Options in Windows 10
If you used to run Windows 7/Vista/XP, you might have known how to get into safe mode by pressing F8 during boot time. Since Windows 8, this feature was disabled by default and got labelled as a legacy feature to increase system boot-up time, not that it affects it much. There are indeed other ways to get into safe mode or access the advanced boot options of windows, but none is as convenient as the F8 key. So, In this tutorial, we will go through the process of enabling this handy feature.feature.

First, we have to launch a Command Prompt window with admin rights. For that, search for cmd
in Windows start menu. When you see Command Prompt as a result, right-click it and choose Run as Administrator
Then run the following command,
bcdedit /set {default} bootmenupolicy legacy
That is all there is to it. You can confirm that it worked by restating your computer and pressing the F8 key during boot time to get to the Advanced Boot Options menu.
Note: This will work on Windows 8, 8.1 and 10.