What’s the best way to mint a NFT art?

A friend of mine has commissioned an art from an artist. Now he wants also to mint that art as a NFT.

He has asked me how to do that. My first thought was minting directly on Opensea contract, but usually NFTs minted in that way aren't worth overtime.

Does anyone know what's the best way to mint a NFT art? Should it be minting a new contract just for that?

I also thought about Tezos, but I don't know much about their environment.