Archer C7 V2 - WAN to LAN with DHCP forwarding

Hi, I have an TP-Link Archer C7 v2 but I need help to setup OpenWRT 19.07.2 .
I have a ISP Modem (at with DHCP server IPv4/IPv6 and I need to set my Archer C7 connect over WAN port to it.
I need that the Archer is avaliable at Static IP (or is the same) and LAN/WLAN clients retreive the IPs (IPv4/IPv6) from Modem DHCP.
Anyone can help me? pls

Have a look at the "dumb access point guide".

Ah okay, I find this guide:
But not configure WAN port....I lost it? or I can set WAN like LAN and bridge all port?

I set router:

I have update the packages but from phone speed 5GHz and 2.4GHz at 1 meter distance the maximum speed is 24Mbps but my connection it's up to 150Mbps.
It's install "ath10k-firmware-qca988x-ct" it's correct? It's a bug?