Is there any benefits in buying raw milk and pasteurizing it at home versus the fresh store-bought whole milk that’s available in supermarkets?
No and unless you happen to have an expensive lab at home you won’t be able to get as tasty/safe results at home. If you don’t get the temperature right you will breed bacteria instead of kill them.
Milk isn’t a rich source of any nutrient that is heat sensitive so regional (and indeed cow) variability will be larger then that between raw and pasteurized milk. Pasteurized is immensely safer which is why raw milk isn’t super common.
The only things added to milk are vitamins A & D if it’s not whole milk.
Healthy bacteria that isn’t lost from the heating process (pasteurized) , more nutrients, isn’t stored in plastic, isn’t run through industrial machines. Plenty of benefits, if you’re gonna go through the hassle of buying raw milk I’d drink it raw