Setup: These steps were performed OpenWRT 23.04.1.
Context: The goal of that manual is to create wireless SSID that will be connected to the Wireguard network as a client. Helpful link - that guide will create a Wireguard interface with kill switch (https://openwrt.org/docs/guide-user/services/vpn/wireguard/extras#kill_switch) In other words, that guide will help you create a deidated wireless SSID that will be connected directly to the wireguard.