I think I might be having some trouble understanding the setup.
When you say you have setup DHCP, I assume you mean scope options 66/67?
Is the WDS server and SCCM configured on the same server?
You don't need
windows deployment services. (or at least you didn't used to need it!)
-that isn't to say that you must not run WDS and SCCM in the same company as you may have different reasons for running each, e.g. deploying servers using WDS and deploying workstations using SCCM. - there is no problem running both, BUT obviously your DHCP scope options can only point to one server on that network, (though in an enterprise you likely have multiple networks, segregating work stations from business servers. so with different DHCP helper options per network (or different DHCP servers on each network) you should be able to accomplish that (if that is what you want.)
There is a guide here to setting up SCCM to deploy images using PXE boot to workstations:
(I know that is for 2012, but it should be similar in 2016.)