what are the five major fields of study in science and explain them?

Answer 1

Chemistry: study of elements, chemicals and their interactions.
Biology : the study of living things (plants, animals, microbes etc)
Geology: The study of the surface of the earth and those things that form it.
Physics: Study of physical phenomena anl laws govening them.

I only know of four. Some say "astronomy" is one but to me, it is a part of physics.

Hope this helps anyway.