https://www.microsoft.com/en-us/evalcenter/evaluate-windows-10-enterprise
The link for Windows 11 is at the bottom of that page.
Click "Download the ISO - Enterprise".
Fill in name, email address, etc., and click Continue.
Select 32-bit or 64-bit version and language and download it.
No product key is needed. It's a 4 GB download.
https://www.microsoft.com/en-in/evalcenter/evaluate-windows-server-2016
At the bottom of the page are links to various Server versions, including 2019 and 2022.
Apparently no product key is needed. It's a 7 GB download.
Last modified 11-5-22