The business report should be considered the written presentation of your innovative idea to an intended recipient.
The specific content and structure will depend on the character of your project and the priorities of your intended recipient.
However, as indicated in the EiTI Handbook it will probably contain:
A description of the business idea and its value proposition.
A market analysis
A feasibility study
The business model
Finance
Risk mitigation.
The structure of a business report may depend on whether your project is framed as a startup project or a project in an existing company. And again a startup project will be described differently depending whether it is a non-profit or a traditional commercial business model. And and the presentation of an internal project in an existing organisation will depend on whether it is a commercial initiative with a new product or e.g. an improvement of internal processes.
However, there are some general guidelines:
If you project is framed as a startup project, where you start up a new business or organsation based on your idea, the framework of a BUSINESS PLAN will probably provide you with a good structure. There are numerous templates for business plans available on the web, so find a few templates and build a customized structure for your purpose - or use a template from your facilitator if he/she provides you with one.
If your project is framed as a project to be implemented in an existing organisation, the framework of a BUSINESS CASE will typically provide you with a good structure. Often simpler than the business plan structure. Again you can easily find templates or structures of a business case on the web and adapt it to your purpose.