Some of my customers refer to their computers as CPUs so it maybe that ernie44 wants to know how to rescue files from one to another or simply (guessing here at the name of the sub-Forum ) network two together.
If you have a router handling your Internet connection, that can act as a hub of a network for two or more computers to exchange data. If you don't have one, you can link the two with an ethernet cable. We need some more details from you as to what you already have.
For a simple network, cable both computers to the router then in each system, right click the C:\ drive and tick to share it in Sharing and Security. Do the same to any specific folders then run the Network Setup Wizard in Control Panel.
Restart both systems and you shold then be able to see either one from the other in My Computer>My Network Places.