Hello @JohnBurke, welcome to the community, we're happy to have you with us!
I recommend using our Marketplace Insights tool to see the current learner demand for your topic(s). You may have to be specific about them, but just keep searching for the subjects you would like to teach about. While we have strict terms around the age of consent to create an account on Udemy, there could still be a large audience for your topic, you'd be surprise how many adults are learning all types of courses on the platform.
Since you have other fields of expertise, I definitely recommend taking some time to explore each topic to see which one would be the best option. You can refer to this support article for more guidance on this.
Best of luck! 😊