Your question seems a little confusing, but I'll do my best...
Yes. DHCP is fully configurable in active directory to assign any addresses for DNS, default gateway or IP that you wish. Same with DNS, you can configure it however you want.
Look into some guides on how to do this in Windows server (or whatever it is you're using) The problem you could be experiencing is having 2 devices (Server and Router perhaps) BOTH offering DHCP, which could create some issues. You should pick either the router or server to provide DHCP but not both.