This offering from Google does NOT provide Windows 10 support. It is ChromeOS, not Windows.
From the article:
ChromeOS has struggled with wider adaptability due to its incompatibility with legacy Windows applications and productivity suites used by businesses.You're getting a different ball of wax entirely, as I read it. You just get to use the old hardware, with ChromeOS.
But beware: ChromeOS is NOT Windows and is incompatible with most Windows programs
Replacing Windows 10 with ChromeOS is an "upgrade" of sorts, but it's not like you're getting Windows 10 "extended support". If you want that past the EOL date, you probably have to be a big company with a Windows Volume License, and you have to fork over some pretty big cash to Microsoft.