On the first question, moisture is to blame for the fact that we fry when it comes into contact with oil, which is heated to a temperature much - much higher than 100 degrees. And on the second question - I cannot offer a 100% effective and reliable way, I myself quickly pull my hand back which I put on the frying pan and immediately quickly cover it with a lid. When I spread a lot of things at once, I try not to preheat the oil to too high a temperature, to reduce the heat.
In fact, it is not the oil itself that "shoots", but the water that gets into it. The fact is that the temperature of the heated oil can reach 160-180 degrees Celsius, while the water temperature is only 100 degrees. A drop of water, falling into such a hot environment, instantly evaporates and, accordingly, sharply increases in volume. The resulting steam literally pushes the oil around it to occupy the volume that is optimal for its temperature. Figuratively speaking, a drop of water explodes; It is this process of instant boiling and evaporation of water that leads to the fact that the oil splashes, "shoots" and generally behaves very aggressively.
You can, of course, fight this. On the one hand, you can slightly lower the temperature at which you fry - in this case, the process of evaporation of water will be slightly less intense. On the other hand, you can use special screens made of metal mesh, which simply will not allow hot (very hot!) Drops of oil to scatter.