I have to appear on stage first - always on the go (6)
I believe the answer is:
active
'on the go' is the definition.
(I've seen this before)
'i have to appear on' is the wordplay.
'i have' becomes 'I've' (contraction of 'I have').
'to appear' becomes 'act' (I've seen this in another clue).
'on' is a charade indicator (letters next to each other).
'ive' after 'act' is 'ACTIVE'.
'stage first always' acts as a link.
This may not be right. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for active that I've seen before include "Lively, working away" , "Not passive" , "kind of voice" , "Not extinct (of volcano)" , "militant" .)