Which year should I go to in high school?

Hello very one i would like to ask an imprtant question so pls feel free to replay me

We are moving to Australia soon as refugee from Malaysia and I'm 17 years old so I'm really confused and don't know if they are going to accept me in high school or if I have to study in a learning centre. I really would like to study in a high school rather than in a learning centre . So my question is: can a student aged 17 enter a high school and if yes is he going to repeat a year or two? And if no, where would he study? And thank you.