The phrase "a young fool" is correct and usable in written English.
It can be used to describe someone who is inexperienced or naive, often in a critical or dismissive manner.
Example: "In his youth, he was often seen as a young fool, making reckless decisions without considering the consequences."
Alternatives: "an inexperienced fool" or "a naive idiot".
Brendan is first seen as a young fool, getting into fights, getting arrested, getting kicked out of his mother's house.
Old-timers like the veteran groom Medicine Ed and the lesbian "gyp" trainer Deucey Gifford think Tommy's a "young fool" but throw in their lot with him anyway.
You're too old to be a young fool and you're too young to be in Depends.
Divorce was discussed, but then a bond was probably sworn between the lords present to remove Darnley by other means: "It was thought expedient and most profitable for the common wealth ... that such a young fool and proud tyrant should not reign or bear rule over them; ... that he should be put off by one way or another; and whosoever should take the deed in hand or do it, they should defend".
Wiest is a delight in her multifaceted role — she giggles under a tablecloth, she clutches a box of money, she makes a play for an awkward young fool, yet she is never entirely unsympathetic.
It was a kind thing to do, not to punish the dog because its owner was a mindless young fool.
The story of a bland young fool who is caught up in patriotic fervor, only to return home maimed and disillusioned but also deepened in spirit, the picture established John Gilbert as a star and gave the newly formed MGM studio its first big hit.
Meanwhile, Jorkal instructs Pierre to persuade his nephew Brandon to retract his testimony and, although Pierre goes off-message by convincing the young fool to testify against himself, the end result is a good one – with Brandon doing his time like a man and the Jorkal name restored in the criminal community.
This poor young fool has nowhere to hide from the scrutiny of public focus.
And: "Eh soft lad, less of the gob" (Really, you impressionable young fool, I would rather you didn't swear so much).
A young woman fooled the governments of three countries.
