For FTCC Somewhere there should be a nbn modem (if the previous tenant has taken it, you'll need to hassle your provider to hassle nbn to hassle them to give it back), and you'll connect your router into that. It looks like this:

https://www.optus.com.au/content/dam/optus/images/km/fixed/NBN_Connection_Device.png

The points in the bedrooms will probably connect back to a patch panel somewhere, usually in the garage. The incoming nbn (phone) line should also be at this patch panel, so you'll be able to connect the nbn modem either directly to it or patch it from there to one of the other rooms. Ditto with your router - it can live in the patch panel or you can patch it to inside the house so you get better wireless coverage.

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