Fund me contract

Fundme.sol

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.18;

import {PriceConvertor} from "./PriceConvertor.sol";

error NotOwner();

contract FundMe {
    using PriceConvertor for uint256;

    uint256 public constant minimumUsd = 5 * 1e18;
    address[] public funders;
    mapping(address => uint256) public addToAmtFunded;
    address public immutable i_admin;

    constructor() {
        i_admin = msg.sender;
    }

    function fund() public payable {
        // Send a min. of 5 dollars.
        require(msg.value.getConversionRate() > 1e18, "didn't send enough wei"); /* 1e18 = 1ETH = 1 * 10 ** 18 Wei */
        funders.push(msg.sender);
        addToAmtFunded[msg.sender] += msg.value;
    }

    function withdraw() public onlyOwner {
        for (uint256 index = 0; index < funders.length; index++) {
            address funder = funders[index];
            addToAmtFunded[funder] = 0;
        }
        // reset the funders array
        funders = new address[](0);
        // withdraw funds from the contract.
        // trasnfer, send, call
        (bool callSuccess, ) = payable(msg.sender).call{
            value: address(this).balance
        }("");
        require(callSuccess, "Call failed");
    }

    receive() external payable {
        fund();
    }

    fallback() external payable {
        fund();
    }

    modifier onlyOwner() {
        // require(msg.sender == i_admin, "SEnder is not owner");
        if (msg.sender != i_admin) {
            revert NotOwner();
        }
        _;
    }
}

PriceConvertor.sol

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.18;

import "https://github.com/smartcontractkit/chainlink/blob/develop/contracts/src/v0.8/shared/interfaces/AggregatorV3Interface.sol";

library PriceConvertor {
    function getConversionRate(uint256 ethAmount) internal view returns(uint256) {
        uint256 ethPrice = getPrice();
        uint256 ethAmtInUsd = (ethPrice * ethAmount) / 1e18;
        return ethAmtInUsd;
    }

    function getPrice() internal view returns(uint256) {
        // Address = 0x694AA1769357215DE4FAC081bf1f309aDC325306
        // ABI - Get the interface.
        AggregatorV3Interface priceFeed = AggregatorV3Interface(0x694AA1769357215DE4FAC081bf1f309aDC325306);
        (,int256 answer,,,) = priceFeed.latestRoundData();
        return uint256(answer * 1e10);
    }
}