If I go on a youth exchange and finish school overseas, does that certification come as equal to my HSC?

I am currently studying full time in a New South Wales public school(Australian public school) but if I finish the equivalent to year 12 overseas on youth exchange, does that mean that I have to repeat year 12 or do anything education related when I get home? Or does it mean that I can just go on with life as if I just finished school in Australia?