Hi Preeti,
SAP recommend to copy the existing co cd and then do the changes as per requirement.
other option is to use country installation program by which you can add template and then create co cd .
please find below link which helps you ..
1. Define, copy, delete, check company code - Financial Accounting Definition - SAP Library
2.Country Installation Program - Country Versions - SAP Library
point 3 will explain steps to create a co cd from scratch.
Regards
Atul