Hard work at school, get some working experience and then apply to cadet programs. Financing your license is very, very last choice.
All the recent cadet programmes are candidate funded, though. Even the BA scheme, where BA guarantees bank loans for candidates (subject to credit checks), requires candidates to repay the funding once employed, so still self funded.
Not sure there's any such thing as truly 'free' training anymore. Maybe in the military. Even then you still have to convert to a UK commercial license once you leave, although I think they provide assistance with this.
Getting a decent backup career going is definitely a sensible approach. Then do a PPL and take it from there. That's what I'm doing
.