Can you do a GCSE course in 6th Form even though it Year 10 and 11?

No, you generally cannot do a GCSE course in 6th Form. Sixth Form is for students studying A-Levels, BTECs, or other post-GCSE qualifications. GCSEs are taken in Years 10 and 11 (ages 14-16). While there might be *very* exceptional circumstances where a school might make an exception for a specific subject, it's highly unusual and not the norm. If you need to retake a GCSE, you'd typically do so through a college or other external provider, not within the 6th Form itself.