How MIUI enters private photo album: enter mobile photo album, drop down on the "photo album" page, and enter the previously set password to enter private photo album.

How to add a picture to a private album: Click on the album picture-three dots in the lower right corner-to add it to a private album.

Method of deleting pictures in private photo album: enter private photo album-click on the picture to be deleted-select "Unlock" icon and select Add to photo album.