As you may have known, there are two different types of NFTs, ERC-721 and ERC-1155. ERC-721 NFTs can be listed either for selling or bidding. ERC-1155 NFTs, however, can only be directly sold and cannot be put up for bidding.
In addition, whether or not to sell the ERC-721 NFT through direct selling or by opening it up for bidding entirely depends on the discretion of the seller who is in possession of the NFT.