Put right hand's fingers inside fish (5)
I believe the answer is:
solve
'put' is the definition.
The answer and definition can be both related to thinking as well as being verbs in their base form.
Maybe you can see a link between them that I can't see?
'right hand's fingers inside fish' is the wordplay.
'right hand's fingers' becomes 'v' (I can't justify this - if you can you should give a lot more credence to this answer).
'inside' indicates putting letters inside.
'fish' becomes 'sole' (sole is a kind of fish).
'v' inserted within 'sole' is 'SOLVE'.
Can you help me to learn more?
(Other definitions for solve that I've seen before include "Figure out the answer" , "Complete crossword" , "Get answer to (a clue)" , "Work out (a problem)" , "Find the answer or explanation" .)