Brave people hiding perhaps? I'm gonna do it! (4,4)
I believe the answer is:
here goes
'i'm gonna do it' is the definition.
I can't tell whether this definition defines the answer.
'brave people hiding perhaps?' is the wordplay.
'brave people' becomes 'heroes' (I've seen this before).
'hiding' indicates putting letters inside.
'perhaps?' becomes 'eg' (for example).
'heroes' placed around 'eg' is 'HERE GOES!'.
Can you help me to learn more?
(Other definitions for here goes that I've seen before include "Let's begin!" , "Informally, I'm about to begin" , "Gee horse (anag.)" , "I'm starting" , "I'm about to start" .)