You have no GCSEs or A levels at all?
As far as I know, most FTOs and airlines require 5 GCSE passes at A* - C, to include maths and english. Some places require two or three A levels, especially the sponsorship schemes.
A GCSE in maths and physics with 3 other subjects you enjoy would be a good plan.
Alternatively, you can find out if your current qualifications have any value to FTOs.
If you want to go down the sponsored route, you'll have to do A levels too.