Is it possible to major in engineering but work in a different field after college?

Engineers are analyses and problem solvers and those characteristics can be used in many other fields. You will still need knowledge in a particular field.

Yes, as the other people that answered said, but to do consulting you must have experience not just schooling. Even if you work in business rather than a technical career, work experience, particularly in your field of interest, is invaluable.

Yes! I am currently working towards a second degree in IT Management. My first degree was Business Admin and I currently work as a project manager. The key is to be able to take the skills you learn and learn how to adapt them to your current role and responsibilities. You will be surprised how much you can do so if you just put a little thought and innovation into it.

yes, you surely can, but having knowledge about the field you are interested in is very important as well.