Since I only have one W10 box,and there's been no need to mess with it:(Also, we moved and that box isn't here yet. )
What do you mean by "reset function"? Are you talking about rolling the system back, or a "reset to factory defaults" in an OEM build?
Also, what build # are you using?
Ah yes, sorry, there is a recovery function in W10 so the user does not have to perform a complete reinstall of the OS.
Instead the OS sort of resets to "default" installation and keeps user files but wipes applications and reverts to Microsoft default settings.
You can find the different options in START -> Settings -> Update & Security -> Recovery
I'm on Windows 10 Pro version 1803 build 17134.407.