<!DOCTYPE html>
<html>
<body>

<script>
myFunction()

function myFunction()
{
     let myElement = document.createElement('p');
     myElement.style.textAlign = "center";
     myElement.style.color = "green";
     myElement.innerHTML = "Ко стаа";
     document.body.appendChild(myElement);
}
</script>

</body>
</html>