Hello aspirant 

As per your query.you want to know about the wbcs exam.please go through the below given link .you would geta more information about it

-https://www.google.co.in/url?q=https://competition.careers360.com/articles/wbcs-2019

There are many coaching in kolkata for wbsc.

Rise foundation.

centre for quality study.

learning plus.

Thanku