It means you have to bet at least 24 times before you will be able to withdraw your potential win + bonus.
Alright 24 times bet, but what should be the bet amount? $10 or any?
Does that matters?
It could be $10 each time for 24 different bets, or you could be doing several all-in bets. It is okay as long as you have wagered at least $240 before requesting the withdrawal.