How to properly configure the router as a repeater?

Question

network hardware

Hello everyone, the situation is this:
There is a main router. It receives the Internet by wire and distributes it via Wi-Fi. Installed in such a way that a twisted pair cable can not get close to it.
There is a PC that is connected via Wi-Fi to the main router.
Task: you need to install a second router as a Wi-Fi repeater of the main one with full access to both the Internet and local resources of the main router.
I tried to do it in two ways:
1. I connect a second twisted-pair router to the PC and distribute Wi-Fi from it. I'm setting up a bridge connection on my PC. The problem is that the network interface to the second router does not receive an IP and does not see anything. The PC itself also loses the possibility of any network interactions, even over Wi-Fi.
2. Through Wi-Fi, connect the second router to the main one. The router connects, but no network interactions occur. In the admin panel of the main router, I see that the second router has an IP assigned. If you do the same with a mobile phone (distribute Wi-Fi from it to a second router), then everything works fine.

Main router: ASUS RT-AX56U, second router: D-Link-300, PC OS: Win 10.
Where to look, where could be the problem?

Answer 1

In theory, on the second router, you need to disable
DHCP

Answer 2

the second router must have the WiFi Repeater function. If not in the main firmware, look at alternative ones, as an option