In Lasors you will find...
You can begin undertaking training towards the issue of a PPL at age 14.
You cannot go solo until you are aged 16 and hold a valid medical certificate (minimum class 2 standard).
You cannot take a skills test until age 17.
However, in theory you can go up for a lesson or experience flight with an instructor at any age. But the time is unloggable and therefore cannot count towards the isssue of a licence.
All you really need to be is tall enough to reach the pedals!
best regards