Despite the end of support, there are still a few official channels through which you may be able to obtain an ISO: Microsoft Software Download Page : Historically, you could visit the Microsoft Windows 8.1 ISO Download page
Bootable USB (recommended; faster than DVD) download windows 8.1 disc image -iso file- - microsoft
: For older hardware, lightweight operating systems like ChromeOS Flex can provide a secure, modern environment for web-based tasks. Despite the end of support, there are still
dism /Apply-Image /ImageFile:"D:\sources\install.wim" /Index:1 /ApplyDir:E:\ Despite the end of support
A. Media Creation Tool (recommended on Windows)
Example decision: