The eldest DC from the way you describe her, must give other parents secret child-envy, wishing to goodness they had as much reason to be proud of their offspring.
She needs somehow to get interests and work, (voluntary is fine) to see what she may be interested in, and it could be anything. Pocket money jobs or volunteering would be perfect. F.E. is ideal and her timing is good, because at last funders are waking up to absurdity of handing half the population worthless academic degrees, just because Tony Liar wanted it (his own son, surprise surprise, is on the bandwagon to reverse that) The fact she is a girl is good, as any sex imbalance is seen to be wrong. The funding imbalance towards 'useless' study was always weird e.g. Germany does not value someone 'doing media studies' but does value engineers, and women in S.T.E.M, and anything practical and useful.
One young woman I knew worked alongside her mum as a volunteer at a disabled children's school, did newspaper rounds, and so made herself ideal for the next part time cashier supermarket job as soon as she could do adult work, always keeping up with her free time work with the disabled children, and did other things I can't remember. She mentioned one evening shift a week as receptionist at the local vet.
I think she took an interest in horses, so she volunteered at the stables, then was a perfect fit for the next (admittedly low paid) job there, assisting disabled youngsters with riding, while she gained some part time study qualification in being a care assistant. Then as soon as there was a paid permanent post at the children's school, it was hers. She was still very young, so they were happy to support her in getting extra teaching certificates while working.
That young woman must be bullet proof, as far as employment goes, anywhere and everywhere. She can already produce a c.v. to knock any competition out of the running, for a large range of jobs. Since covid19 I lost touch with her, but I cannot imagine she won't keep on studying anything she finds interesting, for life, and getting bits of extra experience, and certificates, in what seems an effortless way, because she makes sure her life is busy and active and satisfying.