Update small system components (packages) and load the old into ram until rebooting; I don’t think this is possible on windows.
A/B Image Based Updating; Android and a few Linux distros have this; probably one of the most stable methods.
Live boot updates/Kernel-space Hot Patching; found mostly in Linux servers, and distros with a patched kernel; used mostly for security updates which is what windows is doing here, but Linux can do feature updates this way too.
It comes in 3 forms.