always confused when i should use which one in different condition.
can someone explain to me?
The short answer:

No is mostly an adjective: no peanuts.
Not is an adverb: not happy.
Nope is slang for no when it is a stand-alone adverb denying or refusing something: Are you happy? Nope.
Non- is a prefix which does not stand alone; it is part of other words: nonviolent, nonpareil.
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can explain further.
nope is usually rude or used by those people who knows each othere well(friends)
Nope can be a more firm denial than a simple no. "Did you take those cookies, Anna?" "Nope."

It is used almost exclusively in casual conversation. It would be odd to say "nope" in a business meeting, or in class, but not wrong or insulting to anyone.
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