The OTP (One-Time Password) verification system implemented in index.php uses PHPMailer for sending emails and dotenv for environment variable management. Here's a brief overview of how the system works:

1. Environment Setup:

   • Use Composer to install PHPMailer and PHP dotenv.
   • Create a .env.local file to securely store sensitive information such as email credentials.

2. Database Connection:

   • Establish a connection to a MySQL database to store and manage OTPs associated with user emails.

3. Sending OTP:

   • When a user submits their email, an OTP is generated and stored in the database along with the current timestamp.
   • An email is sent to the user with the OTP using PHPMailer, configured to use Gmail's SMTP server.

4. Verifying OTP:

   • The user submits the received OTP through the web interface.
   • The OTP is verified against the stored value in the database. It checks if the OTP is correct and has not expired (valid for 10 minutes).

5. Frontend:

   • HTML forms are provided for the user to input their email and OTP.
   • jQuery is used to handle form submissions and communicate with the server via AJAX.

1. Install Dependencies:

      composer require phpmailer/phpmailer
      composer require vlucas/phpdotenv

2. Create .env.local File:

   • Place it in the root directory of your project.
   • Add the following content, replacing placeholders with your actual email credentials:

     [email protected]
     MAIL_PASSWORD=your_password
     [email protected]
     MAIL_FROM_NAME=Your Name

This setup ensures that the OTP verification process is secure and efficient, leveraging modern PHP libraries and practices.