Captive portal

[MonkeyFace]

Dear
Along with greeting, I wanted to consult if it is possible to configure a captive portal with 2 levels of authentication, the fact is that I am looking for the way to generate visits to a YouTube channel through a captive portal I was reviewing and I thought about the following

1 ° -Create a captive portal without authentication but with all sites blocked except youtube and a website hosted on a server (Free) where the video we need to generate visits

2 ° - The website created has an address to any site once finished viewing the video, that address can be the access to the second validation where request a user and key, which will be given in a plain text in the same Website, or with a code generator (I am open to suggestions), once entered it will be redirected to the Blog where advertising is shown

The question is?
"Is it possible to do this?"

• Must be done with virtual machines or only with a computer configured with the software?
• is it possible to generate a validation level that blocks all websites except those mentioned above and then enable them?

I leave a basic outline with the comment and I await your comments.