I am looking for a fancy expression to describe people who have no idea what they are doing.
I have a semi-proverb in my mind, but I cannot recall its origins (in particular, I don't think it is English). It essentially translates to:
These morons went to war with a wooden sword.
This supposed to be a (bit sarcastic) metaphor, describing some kind of situation, where the wooden sword represents unpreparedness and/or lack of skills. Those saying this proverb are very well aware of that these people were incompetent (as shown by the morons part).
Is there something similar in English?
Edit: Your idiom has been modernized to "brought a knife to a gunfight". Usually used to describe an event after the fact, though, not as a general description of a person's character. – as @Phil Sweet kindly noted in an earlier comment.
Related, but not a duplicate: Is there another word for unpreparedness?