<html>
<body>
<p id="myH1"></p>
<label>username:</label>
<input id="myText"><br><br>
<label>Age:</label>
<input id="age"><br><br>
<button id="mySubmit">submit</button>
<script>
let username;
let myage;
document.getElementById("mySubmit").onclick = function(){
username = document.getElementById("myText").value;
myage = document.getElementById("age").value;
document.getElementById("myH1").textContent = `Hello ${username} . my age is ${myage}`
}
</script>
</body>
</html>