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I am not sure I really understand what you want to achieve. Can you share more details?
In our demo portal, we have two pages:
I don't think you can "hide" this.
Did you consider to just create two portals?
Instead of using two pages, you could display different content on the first page, based on some parameters in the URL.
Then don't put it as a Page... Integrate that into page 1 code.. upon clicking link show this page
I would recommend two different portals instead of making it complex.