I'm a new noob user of OpenWrt and I can't configure my second router with OpenWrt installed. Router: Linksys WRT1900ACS v2
OpenWrt installed: openwrt-19.07.3-mvebu-cortexa9-linksys_wrt1900acs-squashfs-factory
from Table of Hardware: Firmware downloads
I have the main router connected to the WAN port in my OpenWrt router but there is no internet (everything on default). I used to have Linksys, TP-Link, and DD-WRT firmware working but not OpenWrt.
I want the second router (with OpenWrt) to have a separate network with different subnet IP.
Like this picture
Please help me configure the second router.