You can install a root CA or subordinate CA by using an enterprise or standalone configuration.
To Install and configure Server Core
Adding the CA service by using SetupCA.vbs
Managing CA on a Server Core installation
here is the source where you can find each and every steps for installing CA on windows core server
Source: http://technet.microsoft.com/en-us/library/ff849263(v=ws.10).aspx#BKMK_ManageCA