I am thinking about getting AT&T Fiber internet and do the setup myself.

The fiberoptic wall plug is in the living room of my apartment. I
would like to keep my desktop PC and fiberoptic modem in my bedroom.
The PC has an Ethernet port but no Wi-Fi, so the connection modem/PC
would be via Ethernet cable, that's why I want to keep PC and modem
close to each other.

But I have to find a solution for the connection between the fiberoptic
plug in the living room and the modem in my bedroom.

The idea is to purchase a long Ethernet cable (about 50 ft) to do that.
Do I need to purchase a crossover or a patch Ethernet cable?

I see them both available online...
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tb