The solution:
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title></title>
</head>
<body>
<form>
Number 1: <input type="text" name="num1"><br>
Number 2: <input type="text" name="num2"><br>
Sum: <input type="text" name="sum"><br>
<input type="button" value="Sum" onclick="calcSum()">
</form>
<script>
function calcSum() {
let num1 = document.getElementsByName("num1")[0].value;
let num2 = document.getElementsByName("num2")[0].value;
let sum = Number(num1) + Number(num2);
document.getElementsByName("sum")[0].value = sum;
}
</script>
</body>
</html>
Account
