As Marije mentioned, these missions are not available to the general public.
To be clear, these missions were restricted to users who paid a fee to attend in-person, hands-on training sessions during PegaWorld 2023. Now that PegaWorld 2023 has ended, there is no option for you to pay the attendance fee, as the in-person sessions will no longer be held.
There was an issue in our indexing that allowed these missions to be visible in public search results. We are removing these missions from the search results.