If you format it, it won't do anything until you initiate some recovery or install. So you have to know what to do after formatting.
In fact, there is no need to format. Just do a clean install from the disk or stick you make with the Windows Media Creation tool from https://www.microsoft.com/en-us/software-download/windows10
So what I'm trying to do is format my laptop which right now has Windows 10 on it. When I bought the laptop 3 years ago it came with Windows 8 installed on it. I upgraded for free later on when Windows 10 came out.
What I want to know is that now, after my free upgrade to Windows 10, if I try to format my computer and delete everything on it, will it install Windows 10 automatically, or would it go back and install Windows 8 just like from when it came from the factory?
If it installs Windows 8, what do I have to do to get Windows 10 again.
Thanks for all the help in advance.