Student or Learner
Why Science Words are so difficult ?
"Science words" is unnatural. You could use "words connected with science" or, more probably, "scientific words".
Remember - if you don't use correct capitalisation, punctuation and spacing, anything you write will be incorrect.
Or scientific terms.
I am not a teacher.
As a matter of fact "scientific words" are not so difficult, as long as you have some experience in the corresponding specific scientific field of knowledge. I know many people who find it easier to read/speak/understand specific scientific or technical English rather than usual literature texts or colloquial English. Because the specific words/ideas repeat themselves. Also many "scientific words" are international in the sense that they have common roots and are similar in many different languages.
Scientific terms need to be precise and have an exact meaning. Although some modern areas of science don't derive their words from Latin or Greek, others do, which may make them appear more difficult to you.
When I was in high school, I had to take Latin because I was an honor student. I was not very fond of the requirement. However, when I chose to go into science and medicine, I became very grateful for the background.