Start to eat fish in my official residence (7)
I believe the answer is:
embassy
'official residence' is the definition.
'embassy' can be an answer for 'residence' (I have seen 'Diplomatic residence ' mean 'embassy' so perhaps 'residence' could also mean 'embassy'). I'm not certain of the 'official' bit.
'start to eat fish in my' is the wordplay.
'start to' says to take the initial letters.
'fish' becomes 'bass' (bass is a kind of fish).
'in' means one lot of letters goes inside another.
The initial letter of 'eat' is 'e'.
'bass' going within 'my' is 'mbassy'.
'e'+'mbassy'='EMBASSY'
Can you help me to learn more?
(Other definitions for embassy that I've seen before include "Residence of foreign diplomatic representative" , "Foreign Office" , "senior diplomat's residence ..." , "Where an ambassador lives or works" , "Ambassador's office" .)