RoughVault.sol

// SPDX-License-Identifier: GPL-3.0
pragma solidity 0.8.17;

import "@openzeppelin/contracts/token/ERC20/ERC20.sol";

contract MyToken is ERC20 {
    constructor() ERC20("MyToken", "MTK") {}

    function mint(address to, uint256 amount) public {
        _mint(to, amount);
    }
}

contract RoughVault {
    address public underlyingToken;
    mapping(address => uint256) balanceOf;

    constructor(address _underlyingToken) {
        underlyingToken = _underlyingToken;
    }

    function deposit(uint256 amount) public returns (bool) {
        balanceOf[msg.sender] += amount;
        ERC20(underlyingToken).transferFrom(msg.sender, address(this), amount);
        return true;
    }

    function withdraw(uint256 amount) public payable {
        require(msg.value > 10 gwei, "Give me your money!");
        balanceOf[msg.sender] -= amount;
        ERC20(underlyingToken).transfer(msg.sender, amount);
    }
}

This code snippet is just a toy model, so please DO NOT USE it in any of production environment.