Bitcoin derivatives show a lack of confidence from bulls

I need advice on how to structure my contract. I will have 3 types of NFTs with a limited supply for each, that will be available for purchase through the website. I’m using the ERC21 contract and this is what my mint function looks like:

function mint(uint256 index, address to)         external         whenNotPaused         returns (uint256)     {         if (index == 0) {             uint256 totalMinted = _tokenIdTypeOneCounter.current();             require(                 totalMinted <= NFTTypes[index].maxSupply,                 "All NFTs are minted!"             );              _tokenIdTypeOneCounter.increment();              uint256 tokenID = _tokenIdTypeOneCounter.current();              TokenTypes[tokenID] = index;             _safeMint(to, tokenID);              return tokenID;         }          if (index == 1) {             uint256 totalMinted = _tokenIdTypeTwoCounter.current();             require(                 totalMinted <= NFTTypes[index].maxSupply,                 "All NFTs are minted!"             );              _tokenIdTypeOneCounter.increment();              uint256 tokenID = _tokenIdTypeTwoCounter.current();              TokenTypes[tokenID] = index;             _safeMint(to, tokenID);              return tokenID;         }          if (index == 2) {             uint256 totalMinted = _tokenIdTypeThreeCounter.current();             require(                 totalMinted <= NFTTypes[index].maxSupply,                 "All NFTs are minted!"             );              _tokenIdTypeOneCounter.increment();              uint256 tokenID = _tokenIdTypeThreeCounter.current();              TokenTypes[tokenID] = index;             _safeMint(to, tokenID);              return tokenID;         }          return 0;     } 

Now the question is how do I set my price for each NFT? The price would be dynamic and I will use ponder value for each NFT depending on the current price of the token on the market. I can pull the token price on the front end using the API from chainlink. Do I make the payment using the front end and then when is successful I mint the NFT or do I set the price directly in the smart contract somehow, but the issue is the price should be dynamic and pulled using API?