To ‘mint’ an NFT is to register it on the blockchain and to ascribe ownership of that file to a specific user’s wallet.
To register the NFT, creators have to pay a ‘gas fee’ that covers the computational power required to process transactions on the blockchain.
Minting on Polygon: Verisart covers the transaction fees for NFTs minted on Polygon. Your wallet gets automatically topped up.
Minting on Ethereum: Transaction fees for minting on Ethereum are paid by the minter. You will need to transfer ETH to your minting wallet.