@AK79 Connect PC to one of the LAN port, yellow RJ45 port, open a web browser and connect to 192.168.0.1 or 192.168.1.1, use admin / admin to login. Or simply look for the router model, usually at...

@fnam Try a mobile app to analyze the WiFi around you, review all the channels in 2.4GHz and 5GHz. Next, review the channels on the router for 2.4GHz and 5GHz. If the channels match that around you,...

@Zacky-B.1_ If you have the router model, simply go to tp-link.com -> Support -> search for the model. Next, read the Overview / Specifications / Download sections. In the Download section, download...

@Donny9977 Normally, after changing the router parameters, reboot is not needed, simply hit Save and the setting will apply.

@Mansoor267 The duplex set at automatic shouldn't need changing, the router can detect and adjust accordingly. Check the cable, make sure it's CAT5/6 and the RJ45 has all 8-wires/connectors. Possibly...

@Donny9977 Review the QoS, if on, turn off. Next, review Parental Control and Service Filtering, possibly turn these services off. Also, review the Xbox setting and follow UPnP for the PS4....