I'm thinking if the below setup is possible. My Issue is that I have FritzBox and PC in a different Room and only 1 cable through the wall from where the DSL is. Can my Switch route the DSL connection correctly to the Router (FritzBox) and can then the Router route packages correctly to Xbox and PC?
31 Answer
No. DSL and Ethernet connections use very different kinds of signalling – Ethernet switches won't accept a DSL link, no matter what kind of cable it runs on. (That's the reason DSL modems exist!)
So your DSL connection must go into the modem (FritzBox), and then it can be distributed via Ethernet. (But I don't really see an issue here: why not just swap the modem and the switch in your drawing? If FritzBox is anything like other home routers, it has a built-in 4-port switch anyway, so you can connect the Xbox and the Room 2 cable.)
If the issue is poor Wi-Fi signal, buy a second access point (aka "wireless extender" – or convert a wireless router into one).
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