ERC2981 NFT Royalties Implementation in a ERC721 Marketplace

I've read already many posts regarding this topic, but I just can't wrap my head around this Royalty implementation thing.
Pls help me out, I don't know how I should play with this thing.
what is feeNumerator? _setDefaultRoyalty(address receiver, uint96 feeNumerator)
is it NFT Price? Nft Royalty Percent?
Pls take a look at the following contract and help me with how I can implement NftRoyalty in this contract. Am I doing it right? if not then pls correct me. Thanks.

// SPDX-License-Identifier: MIT
pragma solidity 0.8.8;

import "hardhat/console.sol";
import "@openzeppelin/contracts/access/Ownable.sol";
import "@openzeppelin/contracts/utils/Counters.sol";
import "@openzeppelin/contracts/token/common/ERC2981.sol";
import "@openzeppelin/contracts/token/ERC721/extensions/ERC721URIStorage.sol";

contract PodShip is ERC721URIStorage, ERC2981, Ownable {
    using Counters for Counters.Counter;
    Counters.Counter private _podcastId;
    Counters.Counter private _nftId;

    struct Podcast {
        address nftCreator;
        address nftOwner;
        string nftName;
        string nftDescription;
        uint256 nftPrice;
        uint256 nftRoyaltyPercent;
        uint256 nftId;
        bool listed;
    }


    mapping(uint256 => Podcast) podcastId;

    constructor() ERC721("PodShip NFTs", "PODSHIP") {}

    function mintNft(
        string memory ipfsURI,
        string memory _nftName, 
        string memory _nftDescription, 
        uint256 _nftPrice, 
        uint256 _nftRoyaltyPercent) public returns(uint256) {
            require(_nftPrice > 0, "NFT Price not set correctly");
            require(_nftRoyaltyPercent > 0 && _nftRoyaltyPercent <= 50, "NFT Royalty should be in-between 1 & 50");

            _podcastId.increment();
            _nftId.increment();
            uint256 nft_Id = _nftId.current();

            _safeMint(msg.sender, nft_Id);
            _setTokenURI(nft_Id, ipfsURI);

            podcastId[_podcastId.current()] = Podcast(
            payable(msg.sender), 
            payable(msg.sender), 
            _nftName, 
            _nftDescription, 
            _nftPrice, 
            _nftRoyaltyPercent,
            nft_Id,
            false
        );
        console.log(nft_Id);
        console.log(_podcastId.current());

        return nft_Id;
    }

    function listNFT(uint256 _podcastID) public {
        require(msg.sender == podcastId[_podcastID].nftOwner && msg.sender == podcastId[_podcastID].nftCreator, "Only Owner can list his NFT");
        podcastId[_podcastID].listed = true;
        approve(address(this), podcastId[_podcastID].nftId);
        setApprovalForAll(address(this), true);
        _setDefaultRoyalty(podcastId[_podcastID].nftCreator, uint96(podcastId[_podcastID].nftRoyaltyPercent));
    }

Hi,

Look at the feeNumerator as the percentage of the price that corresponds to the royalties, meaning, royalty is specified as a fraction of sale price. if you take a look at the royaltyInfo function of the royalties contract you will se how the royalty price is computed and returned:


function royaltyInfo(uint256 _tokenId, uint256 _salePrice) public view virtual override returns (address, uint256) {
        RoyaltyInfo memory royalty = _tokenRoyaltyInfo[_tokenId];

        if (royalty.receiver == address(0)) {
            royalty = _defaultRoyaltyInfo;
        }

        uint256 royaltyAmount = (_salePrice * royalty.royaltyFraction) / _feeDenominator();

        return (royalty.receiver, royaltyAmount);
    }

If for example your royalties are going to be 25% of the sale price, you can set your feeNumerator to 25 and override the feeDenominator to 100, and if the sales price is 2000, 25% of that is 500, and if you apply the formula in the function:
(_salePrice * royalty.royaltyFraction) / _feeDenominator()==>(2000 * 25) / 100=500

For more information please take a look at the documentation.

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which function implements the actual transfer of royalties, in my understanding the royaltyInfo function is only responsible for displaying the royalty information.