Since the Pacific Ring of Fire includes a large number of countries, there are many different levels of preparedness for major natural disasters. Therefore, there is no single answer that applies to all countries in the Ring of Fire.
In general, people and countries prepare for disasters in a few different ways. Countries try to educate their people about what to do in case of a disaster. They typically give out information that details what material things you need to survive and what actions you should take in case of a disaster. Countries also try to have plans for how they will use government resources if and when a disaster occurs. Of course, different countries in the Ring of Fire have different amounts of money and different levels of governmental stability. This means that some countries have better plans and give out better information than others.
People who live in areas that are prone to natural disasters typically have their own plans and resources. They will have things like canned food and supplies of drinking water on hand. They will have candles or kerosene lanterns. They will have flashlights. The family will know where these things are in case of emergency. Again, though, people of some countries are more likely to have the money and the information needed to collect these necessities than those in other countries.
Thus, there are some basic ways in which people and governments try to prepare, but not all countries or governments are able to prepare to the same degree.