Microsoft officially ended Mainstream Support for Windows 8.1 on January 9, 2018, and Extended Support ended on January 10, 2023. However, the download servers for installation media remain active because of volume licensing agreements.
Here is how to download without a key:
Next, select your product language (e.g., English). microsoft windows 8.1 iso download 64-bit version -x64-
Rufus will download the official ISO and can even help you create a bootable USB in one go. Microsoft officially ended Mainstream Support for Windows 8