16 yr old support learning at home help

Hi,

Can someone please give advice on where I can find help for my 16 yr old autistic son. He’s been home educated since he was 7 and we’ve tried various online courses and tutors with varying degrees of success. He finds it difficult to remember anything he’s been taught so there’s lots of going round in circles. He also finds it very difficult to engage as is worried about getting the smallest thing wrong. He’s really depressed as never seems to move forward. I think we are just about to lose our current tutor too who he relied on greatly and he is a long way from being able to sit any kind of exam. Is it too late for an ehc plan and what would that help us with? What are his options if exams are just too stressful? Any advice would be really appreciated.