The creation of a bitcoin is nothing more than a record in the contagious book called blockchain, saying that John Doe now owns 12.5 bitcoins, which is how much a miner gets when a block is found .
The first transaction in a transaction block is called the Coinbase transaction. It is in this transaction that the miner creates the bitcoin, making a transaction granting himself 12.5 bitcoins to his public address.
Then it is issued or created?
It's more of a creation. Once a bitcoin is created in the blockchain by a miner, after this miner transfers this bitcoin to another user, this bitcoin does not have any obligation or relation with the miner. Once the bitcoin happens to circulate they are worth it by itself.
If bitcoin was issued, it would have one responsible for it. As a miner has no relation to bitcoin issued, we can say that bitcoins are created and not issued.
My best,
Tim Balabuch,
Designer & Cryptocurrency enthusiast
See my last post: Bitcoin Core & Bitcoin Unlimited: Two different currencies?