How can writing a Review Paper possibly help in the CV of a undergraduate student? I'm  a student of computer science amd I've written a reseaech review article on Fibonacci Sequence which will be published next month in a math journal. All I wanted to know is how will it help in my academic profile and what affects will it make in my CV?
Any work of quality adds value to your profile. If I refer to your question, even the act of writing a review paper, if performed by the rules of the art, is something that you can show and discuss about.

Addtionnaly, if the work has received some sound academic validation (published in a reputed journal) of course this adds to your resume. It adds sometimes more if the topic of your work is close to your background, which seems to be the case here. 

Beware though: it is not common for an undergraduate to be able to write correctly a review paper, esp. on a well-paved topic such as Fibonacci numbers. So, to be blunt, if your paper was accepted almost without review in a local university journal, it might weight less. Or even negatively. 

This really depends on who reads your CV: some will be impressed by the: "published in the Mathematical Journal of Mathematics". Some others may have a look at your paper precisely. If they find that the content is of low level, they might have a more negative opinion than if they were not aware of your paper.