Wifi when you go to any site redirect to your url?

Question

System administration

Firmware OpenWrt, wi-fi. It is necessary for the wifi client to redirect to your url when going to any site. Iptables allows you to redirect only I can’t understand where and what rules to prescribe.
Guys, this topic has been raised many times. and I've been reading about it for a couple of days now and trying it, but it doesn't work for me. if anyone can explain in more detail.