Initial network setup help

Initial setup/configuration help needed. My HA (yellow if it makes a diffence) is on my isp (Verizon) router 192.168.1.XX (can’t see it). My computers, phones, tablets, IOT devices are on my wireless Tp Link mesh network 192.168.68.xx. I think I need to pair these two networks together but not sure how.

And speak to me as if I am 5. I’m 60 and most of this stuff is over my head.

Thanks.

Hi Dave, welcome to this community.
It sounds to me like you have two routers in series, with each working as DHCP server to distribute IP-addresses to their own local LAN network. Something like this:

Does this look familiar?
If not, please provide some more info about your network set-up: which devices and how they are connected.

If your network set-up is as shown, the Verizon router uses the 192.168.1.xx network range in its LAN (LAN1 in my sketch, which is the WAN network for the TP-Link in this case) and the TP-Link router uses the 192.168.68.xx network range in its LAN (LAN2).
And since you connected the HA server to the Verizon router it gets a 192.168.1.xx address. So your IoT devices cannot directly talk to the HA server.

The simplest way to solve this would be to connect your HA server to the TP-Link router LAN interface (LAN2).
The HA server will then get an IP-address from the TP-Link router DHCP server in the 192.168.68.xx range, so in the same range as all your other devices.
Is there a LAN network port available on the TP-Link router?

Thank you Ed! While this is not a perfect solution (for hardware placement), it works!

Much appreciated.