Check out example codes for "upload button in html". It will help you in understanding the concepts better.

Code Example 1

<form action="/action_page.php">
  <input type="file" id="myFile" 
  name="filename">
  <input type="submit">
</form>

Code Example 2

<form action="/action_page.php">
  <input type="file" id="myFile" 
  name="filename">
  <input type="submit">
</form>

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