1) Training from zero experience to Frozen ATPL (which is a commercial pilot's licence with an instrument rating on multi-engine aircraft) - you're looking at not less than say £35-40K, and that's assuming you pass all written exams and flight tests first time.
2) A Class One medical is around £400 and you have to go to Gatwick to the CAA's HQ for this - don't do anything until you've got the medical! There are some horror stories of people going through all the training only to learn that they're colour blind or something that effectively grounds them.
Regarding academic qualifications - some airline's do not specify any requirements for this - if you've managed to pass all 14 written exams then you've displayed you have some level of intelligence - as for not having ANY qualifications, he may find he'll get a grilling at interview as to why he hasn't..... On top of this - chances are he'll be up against similarly qualified pilot's with all sorts of academic qualifications (good 'A' levels/GCSE's and degrees (higher level in some cases)).
Worth considering all the above before taking that step - plus it's not all blue skies, decent night stops and good looking crew!!
All the best...........