The top cream layer, on boiled milk is collected, and allowed to keep for a couple of days, so that the probiotic bacteria can flourish in them. So the day, when you want to make fresh butter, you take all this cream, and put it in the blender with some water. The water is going to separate, and you are going to have lumps of unsalted butter.
Can you make butter from fresh cream? Yes you can, but you are going to note the different quality of the butter made from “stale” cream, as compared to fresh cream butter. That is because fresh cream does not have many lactic acid bacteria in it, yet. But as it is, that cream is going to ferment and produce more and more lactic bacteria.
Also, if you make butter from cream with more lactic bacteria, it is going to increase the shelf life of the final product. That is because the bacteria do not allow any other bacteria to grow in their vicinity.
Buttermilk in the Indian subcontinent is the liquid, which is left over after the cream and the yogurt are churned with water.
The crumbly white food item is pure homemade white butter, while the solid chunky square is cottage cheese.