Fishy novice in a straw hat (7)
I believe the answer is:
bloater
'fishy novice in a straw hat' is the definition.
I can't judge whether this definition defines the answer.
'novice in a straw hat' is the wordplay.
'novice' becomes 'L' (as in a learner driver with L-plates on their car).
'in' means one lot of letters goes inside another.
'a straw hat' becomes 'boater' (synonyms).
'l' going within 'boater' is 'BLOATER'.
Can you help me to learn more?
(Other definitions for bloater that I've seen before include "food" , "Cured herring" , "Fish" , "Buckling" , "that will more than fill one up" .)