Did you know that you can see any post of your WordPress site simply by entering its ID number after the site name:
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This is also the GUID (Globally Unique IDentifier) of the page
To see a page, simply replace the p with page_id
You can similarly create a link to any page or post using the same approach.
I guess the difficult part is to know that ID number. You can see that in the URL field of your browser when you edit the page or post.