1. Because you have not got a AUS/NZ ATPL, you will NOT be exempt the ground school, so find an approved school , study and pass the 14 ATPL EXAMS.
2.If you have 500 hours on the A320, you could convert it , you have not.
3. You will need to pass a GA commercial licence (12 exams to pass) , gain the hours 1500 then sit the ATPL test in a sim.