Bitcoin isn't attached to a state or government, so itu doesn't have a central issuing authority or regulatory body, bassically, that means there's no organizational deciding when to make more bitcoins, digiring out how many to produce, kering track of where they are, so how does bitcoin work as a currency ?
Sadly, Bitcoin is not really taken or used as a currency since it is decentralized and volatile. It is popular as an asset, an investment where in you risk or put your money into so you can earn some profit through time. I will consider bitcoin as a currency if the transacting bitcoin is mainly used for payment or buying stuff online, if bitcoin is accepted by the governments of the world and if the price becomes stable.