First of all sorry if this is a very stupid question, because I have no idea about Ethereum or NFTs. My question is simple: after I minted, for example, an piece of art that I created, what prevents other people from minting another NFT with the same piece of art? It is checked during the minting process the uniqueness of the piece, to ensure that it has not been converted to an NFT already? Thank you
I'm sorry to tell you but there is typically no checks at all about what art or content you upload with your NFT. Any NFT you upload can be re-uploaded by anyone else.
The only way to know if your NFT is the original is by the fact that your NFT was published first.