Can I apply for a job of B.Sc IT with B.Sc CS degree?

Yes, you might but there's not a plenty of scope for it. So its better that you complete post graduation in your respective field.

Nothing is lost worth trying for a job, your application will be scrutinized byu the authorities and if found acceptable, you may get a nod for their recruitment process. But if the authorities have mentioned B Sc CS, then it means.