Help me setup router to WiFi

I want to setup PC -> LAN cable -> archer ax 72 router -> WiFi network.
I can't run cable from main router to ax72.
is this impossible. What about OpenWRT as last option?
There are only these two operation modes;

• Wireless Router Mode In this mode, the router can provide internet access for multiple wired and wireless devices. This mode is required most commonly.
• Access Point Mode (Current) In this mode, the router changes an existing wired (Ethernet) network into a wireless one.