Churchman requires stiffened paper and bent nail (8)
I believe the answer is:
cardinal
'churchman' is the definition.
(I have seen 'Senior churchman' mean 'cardinal' so perhaps 'churchman' could also mean 'cardinal')
'stiffened paper and bent nail' is the wordplay.
'stiffened paper' becomes 'card' (card is a kind of paper. I am not sure about the 'stiffened' bit.).
'and' is a charade indicator (letters next to each other).
'bent' indicates an anagram.
'nail' with letters rearranged gives 'inal'.
'card'+'inal'='CARDINAL'
'requires' is the link.
Can you help me to learn more?
(Other definitions for cardinal that I've seen before include "High-ranking official of the Roman Catholic church" , "Most important number" , "Word to describe one or two" , "Key" , "papal adviser" .)