Which Wi-Fi router is the right one?

I would like to buy a Wi-Fi router to be able to play fortnite pc and so I already have it but now I need a router where I would have a 20 pin to 30 ping in fortnite hilfe and not with how dare you answer

First of all you need internet and that decides which router with WLAN function you can use. WLAN is generally not particularly ping-friendly.

A Fritzbox and comes to your internet provider and take a LAN cable because it has a more stable connection which is good for the ping

The ping is not (exclusively) dependent on the router, but on the speed of your download / upload. If this speed is "slow", a fast router will not increase the ping.

Ping has nothing to do with speed.