What is FOH Departmentalization, kindly explain the procedure

Bit out of context. You need to keep in mind these questions are all coming out of the blue. We have no idea what class you're in, the subject you're doing, etc.

Are you referring to factory overhead? If so, I'm not familiar with the term "departmentalization" used in that context, but it may just be I know it by another name. (Different books can use different names for things, and sometimes authors are actually just making stuff up by how they want to do it.) If you have a book definition (like from the glossary), I might be able to figure out what they're referring to.