Wanting education and mostly ill prepared (6)
I believe the answer is:
unread
'wanting education' is the definition.
(unread can mean uneducated)
'mostly ill prepared' is the wordplay.
'mostly' means to remove the last letter (most but not all of the word).
'ill prepared' becomes 'unready' (I've seen this before).
'unready' with its last letter taken away is 'UNREAD'.
'and' acts as a link.
(Other definitions for unread that I've seen before include "not taken in" , "(Of book) not used" , "Yet to be studied" , "Still to be perused" .)