POC loan (solidity)

loan.sol

pragma solidity >=0.7.0 <0.9.0;

contract loan {
    address payable lender;
    address payable borrower;
    
    uint totalcents;
    uint payed;
    uint interest;
    
    // Loan creation
    constructor (uint _interest, address payable _borrower) payable {
        lender = payable(msg.sender);
        borrower = _borrower;
        totalcents = msg.value + interest;
        interest = _interest;
        payed = 0;
        
        borrower.transfer(msg.value);
    }
     
    function viewbalance() public view returns(uint) {
        return totalcents;
    }
    
    function makepayment() public payable {
        totalcents -= msg.value;
        payed += msg.value;
        
        lender.transfer(msg.value);
    }  
}