Use variables. Make like Variable00X = # of apples you have or something. So at at the beginning of your quest, set Variable00X == 0 . Then everytime the player picks up an apple, add 1 to Variable00X. So, Variable00X=+1, then when you want to have 6 you say, the quest giver or receiver or whatever can use a conditional branch to check if Variable00X =>6 (equal to or greater than 6). And if that variable is equal to or greater than 6 then the quest is completed. Look around for tutorials on variables if you don't know how to use them.