Step 1: You visit this page of Microsoft to download Windows 8.1 ISO: https://www.microsoft.com/en-us/software-download/windows8iso
Step 2: You select Windows 8.1 version which you want to download.
Then you click Confirm
Step 3: You select the product language
Then you click Confirm.
Step 4: You choose the version of Windows 8.1 you want to download 32 bit (x86) or 64 bit (x64) and download it.
When you install Windows 8.1, Windows will ask installation key, you type these keys below:
Windows 8.1 Pro installation key: XHQ8N-C3MCJ-RQXB6-WCHYG-C9WKB
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