Each state has its own processes and requirements for obtaining a painters licence, and specific organisations handle the registration process. You will have to present your qualifications during application.
If you have the required experience and skills, but you don’t have a complete qualification, you may consider using Recognition of Prior Learning as a means to obtain an equivalent qualification without having to spend time, effort and money on unnecessary classroom work.
Please contact your state’s licensing body for up to date information as requirements do change. Skills Certified Australia is not an RTO or licensing body.