hi , as the title says , there is how to do.
1- Upgrade Part
This procedure is useful only if you do an upgrade to Win10 from a legit licensed and activated Win7/8 PC.
a- You must have Win7/8 or above installed and activated with a legit license.
b- Go inside Win7/8
c- Then you must do an upgrade
to windows10 via Windows Update (or via an ISO from Win10 by inserting the media containing Win10 > open > and run "setup.exe").
d- Follow the installation procedure.
e- When the installation is finished, your win7/8 license will be transferred and modified as a Win10 license. this license will automatically activate Win10 when you will connect to internet.
2- Clean Install part:
You must have done a dvd or usb containing the official Windows10 ISO from microsoft.
here the Link : Microsoft's Media Creation Tool
- Be sure to select the proper version , the same one as your in 7/8 version. example: windows 7 or 8 Home = Windows 10 home )
a- insert the dvd or usb containing the Win10 ISO
b- Go into the Boot menu and select the device that will run the ISO, exit and reboot.
c- Now your PC should load the Windows10 installer.
d- Follow the procedure.
all "enter your license" prompts (you should have 2-3 prompts)
f- Once in Windows10 , check if you are activated (go to Control Panel > System > Scroll to bottom) , if not , click the "Activate" button.
g- You should be activated and can npw perform as many clean install as you want.