Make the login/registration work

Please see the website in the attached file. You can see that there is a login/registration option on the right. I need you to make this work with the database and MD5 password so people can register, login and request their password if they forgot it. I also need you to tell me how I can secure subsites with the login control so that not everyone can access the site without being logged on. Please use one of the subpages to demonstrate this. I have no database yet, so you can use any variable you like. I will enter the connection information once I have the files from you. Please ask if you have questions.