Windows 10 Update Issues...

I got locked in one of those update loops. You know what I mean, probably. My Windows 10 would start an automatic update, then fail, and then reset itself to a previous version. This would happen all of the time.

I eventually decided to back everything up on an external drive and simply reinstall Windows 10 from scratch. Then I found out that the CD (or maybe it is a DVD) was lost in our move. I have the ("OEM"?) sticker but the actual product CD has been lost in the move and I can not find it. Does anyone know how I can reinstall the OS with just the product ID etc.?

Someone suggest this link as a way to fix the problem:

https://www.alphr.com/microsoft/1001411/how-to-fix-windows-update-in-win...

So I tried the option on this page that uses

"net stop wuauserv"
and
"net stop bits"

and for a while, I thought I was successful in stopping the update cycle.

But I was wrong. It came back and the computer was again performing an update only to, at the end of the update cycle, automatically reset the OS to en earlier version after it recognized an error.

So, now I am at the point where I want to find a way to back up my system (I have already done this with one of those high capacity external drives) and installing a fresh Operating System. But this takes me back to the problem of not having the CD. Is there some way of doing this with using a USB Thumb Drive? Please advise. Also, what sorts of things do I need to look out for? I imagine I should also back up the registry.