An NFT artist can mint as many NFTs as they like from a single piece of artwork.
NFT art comes in many forms. A one of one piece is a single, unique NFT. A limited edition piece is a limited run of identical NFTs, e.g. a set of 10. An open edition is an unlimited number of identical NFTs, often minted during a limited time period.
There are advantages and disadvantages to each approach. One of one NFT art often debuts at lower values, but can more easily rise over time as the prominence of the artist grows. Open edition NFT art may fetch higher values when minted, but can see those prices decline in the long-term.
When exploring NFT art on popular NFT marketplaces, information such as the number of NFTs available, the floor price, a description of the NFT and more will be presented to the viewer.