To implement user registration and login functionality on your casino site, you'll need to create HTML forms for both processes. These forms should collect user information such as username, password, and email address. Once the forms are created, you'll need to write server-side scripts (typically in PHP) to handle the logic for user registration and authentication. These scripts will interact with a database to store user information securely and validate login credentials. Make sure to implement proper security measures, such as hashing passwords and using SSL encryption, to protect user data.