The Canadian Aviation Regulations list the requirements for certifying aeronautical products and changes to aeronautical products. The regulations define a minimum expectation of technical capability to apply for a type design change.
If you don’t have the required technical abilities, you should source that capability to support your application. One place to look is a Transport Canada delegated Design Approval Organization (DAO) or a Design Approval Representative (DAR).
These people and organizations have various technical capabilities and can also act on behalf of Transport Canada to support you in the certification process, including issuing certain types of approvals.