Read out note Romeo’s hidden inside fan (7)
I believe the answer is:
admirer
'fan' is the definition.
(an admirer is a fan of something)
'read out note romeo's hidden' is the wordplay.
'out' indicates anagramming the letters (out can mean wrong or inaccurate).
'note' becomes 'mi' (as in do-re-mi).
'romeo' becomes 'r' (phonetic alphabet: alpha, bravo, charlie etc.).
'hidden' is an insertion indicator.
'mi'+'r'='mir'
'read' with letters rearranged gives 'ader'.
'ader' enclosing 'mir' is 'ADMIRER'.
'inside' acts as a link.
(Other definitions for admirer that I've seen before include "One who regards (someone) with respect" , "Hopeful lover?" , "Romantic adorer" , "One who thinks highly or romantically of" , "Married (anag) -- lover" .)