Thank you for your help.
When purchasing 6 store-bought kosher challah rolls, that come in one package, is there any requirement to take off bread to separate the dough- even if the dough is already made into bread?
If the rolls have a reliable hechsher, the kosher supervision includes the taking of challah. Since we can assume that the challah was already taken, you don’t have to take off challah again. If you wish to be machmir and take off challah “just in case”, then just take off a little bit (a pinch is enough), without saying a bracha, and then put it into a bag and place it respectfully in the garbage.