Benefit a few and suffer for it (5)
I believe the answer is:
avail
'benefit' is the definition.
(I've seen this before)
'a few and suffer for it' is the wordplay.
'a few' becomes 'v'.
'and' is a charade indicator (letters next to each other).
'suffer' becomes 'ail' (ailing is a kind of suffering).
'for' means one lot of letters go next to another (I've seen this in other clues).
'it' becomes 'a' (I can't explain this - if you can you should believe this answer much more).
'v'+'ail' is 'vail'.
'vail' put after 'a' is 'AVAIL'.
Can you help me to learn more?
(Other definitions for avail that I've seen before include "Be useful" , "Be of value to" , "Be of help or advantage" , "Medal (informal)" , "(Of no) use or benefit" .)