Auto and S are almost the same, both are automatic gears, which belong to fool gears used by people who can't operate.
Video is video, as the name implies.
SCN is a scene selection. In some special occasions, you can choose the corresponding scene to shoot.
DUAL is double anti-shake, which means little.
ASM is a trinity file, which is subdivided into three files: A.S.M. You can search the specific functions of each file online.
The graininess of the card machine will be heavy when shooting at night (ISO is too high). If you want to know clearly, you must borrow a tripod, and the ISO is controlled within 400.