So, if the dollar becomes scrap paper, then what happens to all the money we have in our bank accounts or on hand? Do we in an instant become penniless? Or will it automatically change over to the new standard? And what happens to our bills/credit card & mortgage debts?

I'm just trying to figure out what to do in this situation, need to prepare as much as I can. If we were to take some money out of our bank accounts, will it even be worth anything if all this happens? We are already using up the little we had saved fast right now, not to mention any money coming in. We have some food stocked, but I'm sure we will have family members we will have to help also.