Check out example codes for "how to add a background image in html". It will help you in understanding the concepts better.

Code Example 1

<!-- HTML -->
<div id="imageDiv"></div>

<!-- CSS -->
<style>
  #imageDiv {
	background-image: url('someimage.png');
  }
</style>

Code Example 2

<!-- Background images are better implemented in CSS -->
<!-- but here is how you could do it in HTML in a pinch -->

<head>
  <style>
    .background {
      background-image: url(https://cleananddelicious.com/wp-content/uploads/2016/03/Avocad0-CD.jpg);
    }
  </style>
</head>

<body>
  <div class=background>
    <h1>The background of this div will be an avocado</h1>
  </div>
</body>

Code Example 3

<!-- Code by Scratchy -->
<!-- Twitter: @S_cratchy-->

<head>
  <style>
    body {
      background-image: url(https://wallup.net/wp-content/uploads/2019/09/110394-cats-grey-kittens-fluffy-fat-grass-animals-cat-kitten-baby-cute-748x468.jpg) 
    }
  </style>
  
  <body>
    You have set the background image!
    
    
    
  </body>

Code Example 4

<!DOCTYPE HTML>
<html lang=us>
  <meta charset=UTF-8>
  //the following code within the style tags is CSS.
<style>
  /*this is a body tag. After specifying 
  that we want to affect the whole body,
  we add {}, and write the background color
  we want to change it to. */
  body{background:rgb(255,0,0);
  }
  /* this is a class, which we have named green. we add {}, then
  write the background color we want.*/
  .green{background:green}
   /* this is an id, which we have named blue. we add {}, then
  write the background color we want.*/
  #blue{background:blue}
</style>

<body>
This background is red.
  // you must make sure to note that when you add a background to
  a paragraph, you must add a class or id, name it, then style it 
  as seen above.  with tags HTML already recognizes, however, you 
  don't have to do anything more than shown above.
  <p class="green">
  This background is green.</p>
  <p id="blue">This background is blue.</p>

</body>

</style>
</html>

Code Example 5

background-image: url("image.png");
background-position: center;
background-repeat: no-repeat;
background-size: cover;

Code Example 6

<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>

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