Picture seaside town with fish (7)
I believe the answer is:
portray
'picture' is the definition.
(I've seen this before)
'seaside town with fish' is the wordplay.
'seaside town' becomes 'port' (I can't justify this - if you can you should give a lot more credence to this answer).
'with' says to put letters next to each other.
'fish' becomes 'ray' (ray is a kind of fish).
'port'+'ray'='PORTRAY'
Can you help me to learn more?
(Other definitions for portray that I've seen before include "Use words to describe" , "Depict in art" , "Show" , "Depict, present" , "sketch" .)