Are you opening up your gallery and choosing a photo and then trying the 3 dots to move to an album @CarolMcBain ? If so the option is not there.
Instead I go Into my gallery and then my camera album, and long press on the photo , choose any others I want to move and then press the 3 dots.
Current Phone ~
Samsung Note 20 Ultra 5G SM-N9860_256Gb SnapDragon 865+
Samsung One Ui 3.1/ Android 11.