How do u get a 9 in GCSE french

I don’t take French but I do take German I would say that while you do need to know the vocab if you don’t know any complex structures you won’t get a grade 9 in the writing, you need to practice them so it doesn’t take ages for you to write them in your exam. You also need to know them and be able to form them for your translation.

Duolingo

should i skip to the lessons that i'm learning or start from the start

if you click that you already know some French it will give you a mini test to place where you should be