Which router for PS4?

I have a PS4 and am currently playing with the 3HuiGate router supplied by the provider. But I get kicked out of online games regularly and that's annoying.

Now to my questions:

1.) Would it be enough if I buy a router that I add after my current modem, or should I switch to a router with a built-in modem?

2.) Which router would you recommend?

1) you have an extra modem? From which provider.

2) If you have 3 you need an LTE router…

Do you have poor LTE reception or Wi-Fi problems?

For gaming you use fixed-line fiber optics via which you can then activate WLAN… LTE does not work at all 🤢

Router is enough. From 16k DSL.

Better 25K

I only have one router

How can I test where it fails?

Which one would you recommend?

FritzBox

FritzBox.