The Deadpool page doesn't currently exist. It will be created once the character appears in the MCU in July. I don't think you will have seen a proper page here last year, as creation has been restricted to admin-only for the last five years. Might've been another wiki.

As for your other question, all confirmed characters are listed on the page. Miss Minutes, Mobius, and Loki haven't been confirmed to appear, so they aren't listed.

Hope that answers your questions :)

When Deadpool 3 cast is looked up Wilson, Hiddleston and Strong appear in the cast. Here is a photo.