Is there going to be a need for a separate machine when the paper money is gone?
Indeed it will need a machine. How do you transact everything thru bitcoin? There is no physical thing right? You will need either a cellular phone with an internet connection or a computer. That is still a machine.
As an option, you could use a Bitcoin payment card, though it would still require a centralized payment processor to process transactions. I guess that even if there is no more fiat (not speaking of paper money), the existing infrastructure could already be used for that with a few minor mendings. Anyways, this seems to be the direction offline Bitcoin payments have followed. If paper money is gone, there is no need for ATM's anymore either...
Otherwise, it shouldn't and wouldn't go away
And where could we get that bitcoin payment card? Not every country offers that kind of service and where could I use it.? Still those wuestions will pop up every time a service is offered
You can look here and here for more info. The first article makes a pretty good comparison of six Bitcoin payment cards (though it doesn't include a CoinsBank debit card). These are just like your typical Visa or Mastercard with the difference being that they are not linked to your bank account but rather to your Bitcoin wallet...
As I get it, you can you use them worldwide