https://wizard.openzeppelin.com/#erc721 and https://docs.openzeppelin.com/contracts/4.x/erc721#constructing_an_erc721_token_contract

My721Token.sol

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.20;

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

/// @custom:security-contact mingderwang@me.com
contract My721Token is ERC721URIStorage, Ownable {
    uint256 private _nextTokenId;
    using Counters for Counters.Counter;
    Counters.Counter private _tokenIds;

    constructor(address initialOwner)
        ERC721("My 721 Token", "M721")
        Ownable(initialOwner)
    {}

    function _baseURI() internal pure override returns (string memory) {
        return "https://m721.muzamint.com/";
    }

    function safeMint(address to) public onlyOwner {
        uint256 tokenId = _nextTokenId++;
        _safeMint(to, tokenId);
    }
    
      function awardItem(address player, string memory tokenURI)
        public
        returns (uint256)
    {
        uint256 newItemId = _tokenIds.current();
        _mint(player, newItemId);
        _setTokenURI(newItemId, tokenURI);

        _tokenIds.increment();
        return newItemId;
    }
}