On line security for cameras

I have an Australian NBN NTD connected to a modem/router via ethernet cable and the modem/router communicates throughout the house with other devices via the WIFI (no other ethernet connections). A WIFI extender is used to push the WIFI signal outdoors for a Ring outdoor security camera. I setup the outdoor camera to use the WIFI from the extender whereas the indoor camera uses the WIFI from the modem/router. I have, of course, changed the passwords for both the modem/router and extender but I'm wondering if there are other modem, router, extender or internet settings I need to update to protect this mini network. Any suggestions ?