Bottom line is, learn to play the (any) guitar outright. The chords, the scales and selective picking of the strings, besides rhythm patterns while getting up to tempo. Flamenco can become very fast and involved, when not melodious and romantic.
Kids in Spain are most likely as the kids in Tennesee or Kentucky, that grow up listening and watching their locals play traditional folk, bluegrass and country guitar.
It is a matter of great coordination and speed between the fretboard scales of the left hand actions, while using the fingerstyle picking which goes along for the right hand, at the bridge area.
Much the same (as far as recall and reflex) comparison in exercise 'conditioning' as left hand/right hand control for playing the piano. Getting everythng to fall into place, to express the interpretations of a given piece more completely.
And to ease into the flamenco method, use of a classical guitar is a must, if not preferred, for such music and its appreciations. A great hand, and finger muscle builder (for any guitar player), if nothing else during the experience.
And, don't forget when you get a capo, get one made for the classical gutiar.