I want to know the procedure for the coding standard

answer is same as
http://www.c-sharpcorner.com/Forums/Thread/210599/

See Like for each end every individual webform sholud i take two class file as like(BusinessLogicLayer.Cs & DataAccessLayer) or for the whole project mean to say 90 forms only on this two class files or should take separate for every form

hi,

As per my understanding, you have two class which is common for all other application. right?
so yes you can create separate project to hold these common class files.

this is good idea to keep common file in separate project.