Hello.

You can definitely do company secretary (cs) and bcom together. And the question related to syllabus of cseet (the entrance exam for cs executive) and bcom 1st year..the answer to this is that in cseet management and communication, legal aptitude , logical reasoning , general awareness, all these subjects are there while in bcom all these must not be there . A little portion of management might be there in bcom syllabus.. but no need to worry about the syllabus whether its same  or not . You should definitely give cseet exam . CS is a great field and the cseet exam is the most simple and easy  stage to clear in overall cs course. So go for it.