You're looking for information on downloading Windows 8.1 64-bit using the Media Creation Tool. Here's some helpful text:
The most useful capability of the current Microsoft Windows 8.1 Download Page is its : windows 8.1 download 64 bit media creation tool
Because Microsoft's public links are often down or redirected, many users turn to reputable archives. We need Windows 8.1 - Microsoft Q&A You're looking for information on downloading Windows 8
The original Microsoft Media Creation Tool for Windows 8.1 was called “Windows 8.1 Installation Media Creation Tool” (circa 2013-2015). It had a simple blue interface with just 3 steps. Today, you can replicate 100% of its functionality using the tools above. It had a simple blue interface with just 3 steps
To create 64-bit installation media now, you must use alternative methods: Recommended Alternatives
To ensure you successfully get the working, verify:
Select , choose the 64-bit (x64) architecture, and select your language.