Each client maintains an ARP (Address Resolution Protocol) table which associates the IP address to it's corresponding MAC address

Let's Start Simple, Computer to Computer

Layer 1

Layer 2

Layer 3

Layer 4

Layer 5

Layer 6

Layer 7

Computers can see all 7 layers of the OSI model so seeing layer 2 and 3 as in this case is normal

The ARP function here is sort of redundant since there is only 1 connection