I used to have a rubbish connection to my PS5 through WIFI.
SKY HUB. Black router. Then i got a white sky booster. Connected that to the wifi. Then used a Ethernet cable in the back of that booster to my ps5. Got the full speed of 60mb now. FTTC connection.
If your router is not compatible with the booster. Try one of these Powerline kits. Will get ethernet. Or of you can wire ethernet to the ps5. WIFI is rubbish for PS5. Ethernet works best i find
