Can we help to lower the percentage of natural disasters? If yes, then what the methods to lower it?

Most of them, such as volcanoes, no.
Some of them are the result of man-made climate change. Yes to those.
You can take it from there - weather patterns are a very complex topic and I'm not going to write the book for you.

Seriously, what do YOU think ?

Most great natural disasters cannot be reduced; Earthquakes, volcanoes. The last Ice Age occurred when the earth was sparsely occupied. The asteroid that struck the earth and likely wiped out much of natural life occurred well before man. Man had no influence on some of the worst hurricanes and tornados. Global warming is/ may be due to man but the earth has been much warmer, they have fossilized palm trees on Greenland and Antarctica.

The Suns going to burn out eventually, that's something else to worry about too.