If you are running a previous version of Windows, of the same bit-ness (64-bit on 64-bit, etc.), then you can download the MS Windows Upgrade Assistant, which will automagically download the upgrade, and install it.
If you don't have any OS on there at all, then you need a PXE Boot server, or WIM Image boot server, to get the PC to boot off of a remote OS image, and then install the OS over the network to the internal HDD or SSD.
It's much, much, easier, just to use a USB flash drive that is bootable, with the necessary OS installation files on it. One of these can be created with the MS Media Creation Tool.