Cablenet 20cm USB 3.1c Male - Ethernet RJ45 Female Tailed

The current trend of making laptops thinner now means that many of the connectivity options you are used to seeing have been replaced by a single USB Type C socket.

Simply attach this unit to the USB Type C connector on the laptop and you will gain a Gigabit RJ45 (10/100/1000) socket.
You will then just need to connect to a network using the appropriate cable.