Find Embedded product key
https://neosmart.net/blog/2014/windows-10-embedded-product-key-tool/

key finder
https://www.magicaljellybean.com/keyfinder/

http://dellwindowsreinstallationguide.com/download-windows-8-1-retail-and-oem-iso/

Bascule windows entreprise a pro
http://les2t.fr/windows-passer-dune-version-entreprise-a-une-version-professional/
https://searchenterprisedesktop.techtarget.com/blog/Windows-Enterprise-Desktop/EIcfg-and-PIDtxt-Install-Windows-License-Info

use tool named UltraISO to deposit them directly inside an ISO

EI.CFG dans \sources

For {Edition ID} use the name of the edition you’re installing (Home, Pro, Enterprise, or Education). For {Channel} the value must either be “OEM” or “Retail”. Unless you’re an OEM, that means retail. If you’re using a volume license, the value for {Volume License} must be 1, otherwise 0 (zero).

Creating PID.txt

If you thought the EI.cfg file was easy — and it is — PID.txt is simpler yet. It contains two lines. The first reads “[PID]” (omit the quotes, they’re just there to show you what to type. The second reads “Value=XXXXX-XXXXX-XXXXX-XXXXX-XXXXX” where you’ll substitute an actual and valid 25-character Windows key for the string of X’s