Creation of a registration-authorization and search system on the site

There is a website written using bootstrap on html5. The following should be done:
- write or configure a ready-made search script for the site, if you have one.
- Make a registration / authorization on the site, so that after it the registered user can download specific several files on the page.

I mean. An unregistered user visits a certain section of the site and sees a registration form in it. Then it is registered, logged in and instead sees links to the desired files on the site.