First, congratulations for thinking ahead about career choices! Many people fail to do that, and later regret not following the right educational path to get where they want to be in the future.
Second, let me reassure you that there are plenty of jobs that combine engineering and commerce. I even wrote an article published by the International Institute of Electrical Engineering (IEEE) that is about how to map business strategy to resource allocation in an e-commerce environment. If you can navigate both worlds, understanding the business and technical aspects of how companies operate, you will have many opportunities open for you--it's the combination of knowledge of both areas that led me to a successful career as an IT business analysis consultant.
I don't think you need to find a course that combines engineering and commerce to achieve your goal (I only studied Electrical Engineering and developed knowledge about business and commerce while working as a systems analyst). My suggestion would be for you to do some research to find an area in engineering that appeals to you, and go from there.
While studying engineering, be serious about finding relevant internship opportunities -- you should find good internship options that will allow you to learn about commerce from these experiences (yes, even if the internship is on the technical side). You can also get help from an adviser about what classes you could take to develop valuable skills in the area of commerce, but I wouldn't worry too much about this aspect. In my experience, a good engineering foundation will open many opportunities for you to get exposure to the business, and these things combined will make you a very attractive job candidate for the type of career you are envisioning.
Good luck, and write again if you have more questions!