The Cisco Meraki MX67W is a security appliance with integrated wireless capabilities. It can connect directly to an internet source such as a DSL modem, cable modem, or a fiber termination point like your NBN FTTC Network Connection Device (NCD).
In the case of the NBN FTTC NCD, it essentially acts as a modem, converting the fiber signal from the NBN network into a format that can be used by your devices.
You should be able to connect the MX67W directly to the NCD using an Ethernet cable. The Ethernet cable should be connected to the LAN port of the NCD and to the Internet (WAN) port of the MX67W.
After connecting the devices, you will need to configure the MX67W through the Meraki dashboard to ensure it is correctly set up for your network.
Keep in mind that if your ISP requires specific settings such as PPPoE or VLAN tagging, you would have to configure those settings in the MX67W dashboard settings.
As always, make sure to consult the specific documentation provided by your ISP (NBN Co) and equipment manufacturer (Cisco Meraki) to ensure correct setup.