NFTs are created on a blockchain by using smart contracts. These contracts are coded to represent ownership of an asset. The cost of creating an NFT depends on the type of token being created and what it is being used for.
The cost to create an NFT also depends on the platform it will be released on.
The OpenSea fee for February 2022 is 2.5% or about 200 USD (0.05 ETH) to put NFT up for sale. The second option is to pay a minimum gas price of 0.02 ETH (80 USD) to initialize your wallet in OpenSea, after which there is no commission.
Each NFT in Binance Smart Chain involves a creation fee of 0.005 BNB.