In Australia, Year 9 students (or sometimes Year 8) choose subjects for Year 10, and Year 10 students choose for Year 11-12.
This feels momentous ("You're choosing your career!"). It's not, quite. But it matters because strong performance in Year 11-12 affects uni entry.
That said: most Australian unis accept broad pathways. A Year 9 choice isn't life-locking. Teens can change direction.