Frightened beginning, then went ahead (8)
I believe the answer is:
startled
'frightened' is the definition.
(thesaurus)
'beginning then went ahead' is the wordplay.
'beginning' becomes 'start' (start is a kind of beginning).
'then' is a charade indicator (letters next to each other).
'went ahead' becomes 'led' (I've seen this before).
'start'+'led'='STARTLED'
(Other definitions for startled that I've seen before include "Caused sudden alarm" , "Affrighted" , "Taken aback" , "Scared" , "Suddenly alarmed" .)