Which island is a part of the Australian Continent?
The largest island in the Australian continent is Tasmania, which is one of the Australian States. But there are thousands of other smaller islands.
Auckland New Zealand is not on any continent. In fact it is far isolated from any of the 6 continents. It is on the North Island of New Zealand in the south west Pacific Ocean. New Zealand is part of Oceania, which is considered - erroneously - by some to be a continent. It is not part of the Australian continent.