Step 1 :- Use a crossover cable to share files from PC to PC and connect that to the two PCs.
Step 2 :- enable the network sharing options in the control panel of the two computers.
Step 3 :- Assign two different IP addresses to the two computers from the properties of the Ethernet in control panel. ex :- PC1 - 192.168.1.2 , PC2 - 192.168.1.3
Step 4 :- after that Right click the file/folder in PC1 that needed to be share and go through the option