Set up LAN with internet gateway ask-ncq1338

I just set up my internet gateway ask-ncq1338 today using wireless and wired connections without issue. But how do I set up a LAN so that my computers can see each other, i.e. view and move files, etc. Currently I have Computer A connected to Ethernet port A and Computer B connect to Ethernet port B but they cannot see each other.

According to Netgear, file sharing should be a standard feature for an internet gateway.

Or do I need to buy a router again? Verizon support was absolutely totally useless.

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