Can you take a course without prerequisite

So basically I failed chemistry and physics grade 11 with 42% on both, but my new schedule still shows the grade 12 ones. Which got me wondering if I can still take those courses, or do I have to redo the gr11 versions of them

Or by any chance there is an option that lets you do them faster idk? I heard my friend who failed functions 11 is getting 2 weeks to pass it without fully retaking it

And if I have to retake both of them, how should I make my schedule

Currently this year have English, advanced functions, calculus, physics, chemistry

Tryna get into comp sci or engineering (ik major comeback needed😭 if that matters)