Use .innerHTML
to replace elements within a DOM object.
function ReplaceText(){
document.getElementById("mytext").innerHTML = "My new text";
}
<html>
<head>
</head>
<body>
<div id="mytext">
My text
</div>
<button id="replace" onclick="ReplaceText()"> Replace Text </button>
</body>
</html>
solved Buttons in HTML/Javascript [closed]