Not prepared and not studied! Why, for crying out loud? (7)
I believe the answer is:
unready
'not prepared' is the definition.
(I've seen this in another clue)
'not studied why for crying out loud?' is the wordplay.
'not' becomes 'un' (prefix meaning 'not').
'studied' becomes 'read' (to read a subject is to study it at university).
'for crying out loud?' indicates a 'sounds like' (homophone) clue.
'why' is a homophone of 'y'.
'un'+'read'+'y'='UNREADY'
'and' is the link.
(Other definitions for unready that I've seen before include "ill-advised in a king" , "Disobedient in a scout" , "Ill prepared" , "Like one English king" , "Ethelread the ..." .)