hide a post
choose hide in the three dots menu, or tap the lock at the top of an open post. the post leaves your home feed and moves into the built-in private folder in your library.
see hidden posts
open the library tab, turn on show private folders (face id needed), and open the private folder.
unhide
open the post in the private folder and choose unhide. it returns to your home feed.
good to know
hiding is for privacy on your own phone. it is not encryption. anyone who can unlock your phone and pass face id can see your private folders.