In pain, maybe I've to accomplish something (7)
I believe the answer is:
achieve
'accomplish something' is the definition.
I can't judge whether this defines the answer.
'in pain maybe i've' is the wordplay.
'in' is an insertion indicator.
'pain' becomes 'ache' (ache is a kind of pain).
'maybe' indicates an anagram.
'ive' anagrammed gives 'iev'.
'ache' enclosing 'iev' is 'ACHIEVE'.
'to' is the link.
Can you help me to learn more?
(Other definitions for achieve that I've seen before include "Successfully bring off" , "Skilfully bring about" , "Have ice (anag.)" , "Accomplish, gain by effort" , "Produce" .)