Creating multilevel CSV file

I am going to create a multi-level CSV file with only one work-book in MS-Excel, but I am not able to that. Please help me how to do it?
For example,
suppose there is an OFFER
this OFFER has several information such as general Info, Offer_type, Billing Rules, Items etc
again, suppose Offer_type has several parts like Purchase, Trial, trial_&_purchase etc.
Trial offer has again some parts like trial_period, upgrade_from_trial etc.

So, now I want to create a csv file by taking all these information. May be i'm a stupid so I am not able to that but still I want to know how to do it.?

Hi,

To format a csv file with specific data, you will have to create a plugin, and then get and format the data to have desired csv file.
So it require good php skills.

Thanks for your reply.

But at first I want to create a CSV file manually after that I will import this file and again export same file as it is needed in my project. So I think first I need knowledge to create a Tree Look csv file which will be parsed in the coding section.

So, please let me know how to create that Tree Look *.CSV file in excel?