How to create multi step form using php

How can I implement a step-by-step form submission process using PHP? 

Begin by creating an HTML form with multiple sections or steps, each having its set of form fields. Implement appropriate navigation buttons, such as 'Next,' to facilitate movement between the steps.

To store the form data submitted at each step, various methods can be employed, such as sessions. However, in this blog, I will demonstrate how to pass data using form fields(hidden fields).

Upon completion of all the steps, submit the final step. Validate the collected data and perform any necessary actions, such as storing it permanently in a database

Implementing a multi-step form with PHP and hidden fields typically involves breaking down a lengthy form into multiple steps and storing the data temporarily between steps. Hidden fields can be used to persist data across these steps. Here's a simple example using PHP and HTML:

<?php
if(isset($_POST['submit'])) { 
  echo "<p>Thankyou!</p>";
  echo "Your username: ".$_POST['username']."<br>";
  echo "Your mobile number: ".$_POST['mobile_number']."<br>";
  echo "Your Password: ".$_POST['password']."<br>";
}
else {
  if(isset($_POST['step-2'])) { ?>
    <form id="step-2" method="post" action="">
      <input type="username" name="username" placeholder="Enter your username" required>
      <!-- Pass a submitted data to next form -->
      <input type="hidden" name="mobile_number" required value="<?= $_POST['mobile_number'] ?>">
      <input type="submit" name="step-3" value="next">
    </form>
  <?php } 
  else if (isset($_POST['step-3'])) { ?>
    <form id="step-3" method="post" action="">
      <input type="password" name="password" placeholder="Enter your password" required><br><br>
      <input type="hidden" name="username" value="<?= $_POST['username']; ?>">
      <input type="hidden" name="mobile_number" value="<?= $_POST['mobile_number']; ?>">
      <input type="submit" name="submit" value="Register">
    </form>
  <?php }
  else { ?>
    <form id="step-1" method="post" action="">
      <input type="number" name="mobile_number" placeholder="Enter your mobile number" required>
      <br><br>
      <input type="submit" name="step-2" value="next">
  </form>
  <?php } 
}

The form data is processed in a separate PHP file (e.g., form.php). You'll need to implement the processing logic there based on your requirements.

Remember to handle the form submissions and process the data securely, validating and sanitizing user input to prevent security vulnerabilities like SQL injection or cross-site scripting (XSS).

Thank You!