Conversation so far:
What happened with The Monkees were on television?
In assigning instruments for purposes of the television show, a dilemma arose as to which of the four would be the drummer.
How long did this dilemnna last?
Thus, Dolenz (who only knew how to play the guitar) was assigned to become the drummer.

Question: When did they officially have a concert and went on stage?
Self-contained rewrite: When did The Monkees officially have a concert and went on stage?