what other certs do you have?
do you have anything you've already achieved that you think could be monitized? art, market skills ect.
Do you want it to be a laboring business or more like office work.
do you want to work from home?
what type of return do you want? is it a fun side business or full time work?
generate a whole heap of questions like these and answer them. Even if you are still not sure what exactly you want it to be you have a better picture. then hang that picture up against reality if it lines up well you are probably on the right track and can continue refining your idea.