Hello, I have a cable coming from roof into my router through some power/data dongle - the cable from roof goes in there, you power it and from that goes another ethernet cable into the router. The router has 4 ports and from one of them is going ethernet to my PC. We have brick walls so just 2 rooms, where my chromecast is, the wifi isn't really good enough to stream HD constantly. Now for my question: I'd like to use the thing that carries ethernet over the powerline, but can I just plug in another ethernet cable from my router and then on the other side put it into a new router and it would work? or do I have to give up on my first router and replace it with a switch? anything else I should look for?
Thanks for all your answers, sorry I'm not good at networking.
P.S.: https://www.amazon.com/s?k=ethernet+over+power&crid=3O7TPR2NO9UEW&sprefix=ethernet+over+%2Caps%2C242&ref=nb_sb_ss_i_1_14 something like this, just for our socket.