Welcome to Adelaide, Bhupen008
Registar with Medicare, you can do this at the Centerlink.
SA Ambulance cover, you can apply for this at a Post Office. You can also get private health care as additional. Can't help you with this, as we just have Medicare and SA ambulance cover.
You will need to gather your 100 points for ID, necessary for rental etc.
There are loads of recruitment agencies it the city. Get to the local library for the free wifi.
Snifter has put a very helpful thread on schools in the kids section with excellent links.
Get exploring and enjoy