How to fly internationally from Sydney airport

Hey so I've never flown internationally before but have booked flights in May to visit relatives. I don't know how we do things here

What's the process going through Sydney airport?

Do I need any other forms of ID other than the passport, or do I need drivers licence or Medicare card? If I just have plane tickets on my phone, do I need them printed out or can they be qr scanned?

I have some prescription medications, is it ok that I pack them in my big suitcase/checked baggage or do I have to show them with drs note to someone?

If I have hair clips or jeans/jacket zipper is security going to flag me for metal detection?

Is there anything else I'm forgetting?

Thankyou in advance