Is this possible with custom code?

Hello! I'm working on building a site for a friend. They basically want a simple landing home page that has an image which links to a password protected page that hosts an embedded video. Below the video, they want to have a "login" button which will lead certain individuals to a designated member area (each individual will have their own custom member area with unique content). Is it possible to put the login button/link in a block below a video? And is it possible to have users sign up with a username and password rather than an email? My friend would like to pre-assign usernames and passwords for each user (they can then change the passwords after the first login).