You can´t just install a datacenter version and sell vps. You need a special license for that as the Windows Datacenter EULA prohibits the rental or "subselling" of virtual machines. The license for internet service providers can only be rented from official microsoft distributors so you need to contact one of those.Visit: https://www.microsoft.com/en-sg/Licensing/licensing-programs/spla-program?activetab=spla-program%3aprimaryr2 for more information.
Saying that, if you are able to move a license to another server depends which form of windows server you have installed. If it is an OEM version, it won´t work (or at least is not legal). This licenses are bound to the hardware where first activated on.