Well, it is technically "piracy" but it's amateur piracy. No need to get fancy with torrents and VPNs or whatnot. Just download the software and... not pay.
Well given op said download it from microsoft then yes it will be riddled with spyware but that's the genuine windows experience® for you...
The downvoted guy you replied to is right. You can download the (genuine) iso off microsoft and install it without paying M$ anything, it will work fine other than not being able to change wallpaper etc.
If that small restriction annoys you the MAS (linked elsewhere in thread) is the answer