Not quite that simple...you can do a clean installation when installing win10 the first time. Create a usb key of windows from microsoft, from win 8.1 start the installation procedure that is on the usb key, don't enter a key, and pick clean installation.
"*Your goal is* to get to the screen with this full range of options:"
This is the Recovery Screen.
How we got here with these options is not clear.
Let the games begin...
Sometimes what they don't tell you is more important than what they do tell you.