Question: So I have a new PC build that I’m close to putting together but I would like to transfer all my hard drives from the old one to the new one. The new motherboard is:

Asus TUF GAMING X570-PLUS

The old one is:

ASRock Z77 Pro4

So do I need to deactivate windows 10? I have the product key written down and I know how to deactivate it. It’s linked to my Microsoft account.

Answer:

So can I back up the entirety of my C drive (where I installed windows 10) or would that complicate things?

Major complications, and won’t work. A backup of the entirety of the C can’t work with the new hardware.
Backup your personal data, and copy that back into the new OS install.