i’m a new beginner and exactly don’t know where to start that create smart contract of simple auction that combine with ERC721 . Hope any resource can help, like article , medium, tutorial, sample code .
There’s an example auction in the Solidity documentation. I’ve also found this and this examples, although rather old. You could start there, then later check Contract’s ERC721 documentation. The main difference with this auction is that instead of ether, it will be transferring the ERC721.
For auctions and sales you may just want to use existing marketplaces such as OpenSea and you can focus on your ERC721. See Create an NFT and deploy to a public testnet, using Truffle