I'm not debating the legality, but rather the validity.
A valid Win 10 install, created with the current MediaCreation tool, will absolutely not impart any virus.
Either you're getting it from somewhere not valid, or you're installing the OS incorrectly.
MediaCreatin tool here:
https
/www.microsoft.com/en-us/software-download/windows10
Have only one drive connected.
Boot from that USB or DVD.
During the install delete ALL existing partitions on the target drive.
How to do a CLEAN installation of Windows 10
Unless you have some incredibly rare BIOS virus (you don't)...a virus will not survive deleting all the existing partitions.
If you're really concerned (and this is not an SSD),
DBAN.
That will absolutely...