Hello. You can learn more about this in the documentation.

Or in my paid video tutorials ("Tutorial 20. User Automatic Registration").

Hi Nektarios, 

thank you for getting in touch. 

You can manage this with the registration function of WebSite X5, which can be either automatically or manually managed. 

As far as the manual registration is concerned, once you has password-protected a page, you place a registration form on a public page so people can send you their registration requests. You then create manually the users, enable them for the access to the password-protected page and provide them with the login credentials. 

Alternatively, you can manage the registration automatically. Here's a dedicated guide: https://guide.websitex5.com/en/support/solutions/articles/44001271386

Thanks!