How do i find out what the original operating system was on my laptop computer?

[Anthony1881]

I have a failed update that blocks other updates and eventually sticks my pc on the "Getting Windows ready, Don't turn off your computer" page.  After 12 hours of waiting, the only solution was a forced shutdown and then a reset, loosing all my software and having to reload it.  I have done this four times.  So I would like to be able to get an OS disk with Windows 8.1, but the ones I see available talk about a key to make them work.  Therefore, I am trying to find out what my computer's original operating system was.

[Huffer]

Specs say Windows 10 Home 64 bit:

https://support.hp.com/us-en/document/c04797004

Before you knock yourself out any more you need to run a hardware diagnostic on the hard drive and memory. No reason you should need to do 4 restores in a row. Something ain't right. 

Tap esc as you power up then F2 and run the long tests on RAM and hard drive. 

You can download a free Windows 10 disk from Microsoft Media Creation Tool site (google it just like that) and you need no Key Code to reactivate. Your credentials are embedded in the BIOS or stored on Microsoft's activation servers. 

But the immediate problem is to get Windows back on the computer.