Adam,
If you joined as a soldier, you could join any Corps or Regiment, however, the AAC would be the logical one. You the need to be a Lance Corporal with a recommendation for promotion below the age of 29 to apply for pilot training. You would then be sent to Cranwell for the aptitude tests and then do 3 weeks of flying at Wallop to assess your suitability. Once you have passed these you the go to the Selection Board. They are very keen to attract young NCO pilots, so it is not a huge hurdle. Then it is onto the Army pilots course, where you get your wings in 14 months, and are streamed either Apache, Lynx or Islander.
Good luck with your future.
BS