Directions for newcomer on XBEE S1 needed

Hi, I started my journey with HA few days ago, trying to migrate my previous custom solution into it and got stuck with my XBee network.
I have XBee USB modem plugged into Raspbery PI4B (where HA is running), few relay controller boards on XBee network (of that type), now reading Zigbee integration documentation, forum posts related to it, but can not figure out how to map HA switch to a specific relay on one of the banks on the board.
In my previous project I was simply addressing it with board network address, bank and relay identifiers with AT command.

Any help or guidelines will be very appreciated.