There is no limitation on when you can start learning to fly when accompanied by a flight instructor, but you must be 15 years old to fly solo.

Whilst under the supervision of a flight school, you do not need a licence. However, you will need an aviation reference number (ARN) prior to flying solo.

You will need a CASA Class 1 or 2 medical certificate prior to flying solo

A recreational aircraft is an aircraft that has a maximum take-off weight of less than 1500kg, is not turbine or rocket powered and is certified for single pilot operations.