Hi Sudipta
Business process wise if you consider the flow is more or less same. Example planning, MRP execution. production/process order creation etc. But feature wise they carry different functionalities. In process industry you have different master data to meet business requirements, batch management (though could be in both but usage wise could be different), process instruction sheets to capture data as per different phases and business requirement.
I would recommend you to go through the As-IS documents, configuration documents etc. for your support project to understand the functionality used by the client.
Now as a support consultant of course you need to resolve daily tickets irrespective of functionality and check various reports etc. depending upon the service agreement between your client and your company. You need to understand what you have to support and monitor on a daily basis as per agreement.
I hope this gives you an overview. If this answers your question follow How to close a discussion and why else raise your concern.
Regards
Rahul