What kind of sandpaper does automotive sheet metal paint use?

what sandpaper should be used in what situations, such as; Polish putty with 6 mesh for the first time, 32 mesh for the second time, and 8 mesh for the third time: if you just polish the paint skin and then paint it with 1 mesh sandpaper, if the brightness is not up after painting, you can polish it evenly with 2 mesh sandpaper and polish it with a polishing machine!