bind9 (listen-on)

I want my dns server to only listen to the external network. Because I had to use another dns server (dnsmasq) for the internal network and it would respond to the demands coming from the internal network. This is my obligation to install the virtualmin openvpn at the same time I want to set up pihole. but I can't reach my web sites when I tell bind9 to listen to the outside network.

where do you think I'm making a mistake. Or is it so stupid that I do :)