How to set up Ethernet port

[Biest]

So for whatever reason the builder forgot to hook up my bedroom with Ethernet how do I split 1 port into 2? This is going to be from a already established Ethernet port.

[Electronics Wizardy]

switch get this https://www.amazon.com/NETGEAR-5-Port-Gigabit-Desktop-Switch/dp/B00QR6XFHQ/ref=pd_lpo_147_tr_t_3?_encoding=UTF8&psc=1&refRID=Z6W1JW7W5NCAS626B8K5

[Oshino Shinobu]

An unmanaged gigabit switch is what you want. You can pick them up for $15 or so with 5 ports.