set background image in CSS and link in html code example
Example 1: css background image
background-image: url("image.png");
background-position: center;
background-repeat: no-repeat;
background-size: cover;
Example 2: inserting a image in html backgound
<html>
<style>
body
{
background-color: url('url from web'); /* replace "url from the web" with your url*/
}
</style>
<body>
<!-- Your body displayed with the picture-->
<h1></h1>
</body>
</html>