Wow, that’s a hard set of GCSEs you got there. I think what you need to pick is something you enjoy because it’s so so so important to have a subject that you can look forward to, enjoy learning in, and then your positive attitude from that will last into your other subjects and really help you get through the revision and tough patches. That would be my priority if I could go back at least. Also, think about your strengths, how focused you are and how organised you can be.