Poking about in Moreton Bay and the protected waters between the Gold Coast Seaway and Caloundra will give you the opportunity to learn the ropes then if you can make it up into the Great Sandy Straits you have another large body of protected waters and from there you can day sail it all the way to Cairns or further north. There are lots of VMRs you can get local information
reports and if you graduate to more remote
coasts there are weather
reports from the Met Bureau via HF radio
With the semi protected waters inside the reef and lots of re-supply places and anchorages
and good weather the coast of Queensland
is probably one of the better places in the world to take up and learn the small vessel cruising game
Unfortunately the Shiela Net HF radio
network on 8161 at 0800 ceased operation a few years ago, it was a great place to meet other cruisers who you could later introduce yourself to in various anchorages
. You might join the Shag Island Yacht Club, it is a fun thing and I think they have a radio
network and roundup at the Gloucester Passage
every year where you could meet other cruisers.
Good luck with your plans and a cat is an excellent choice for cruising northern Australian waters.