1. Analyse yourself and find out the topic you are most expert in, first make a course on it, mostly those courses run in which instructor is knowledgeable and the content is great, if it is not demanded much still if you bring your best it will run
2. Go to udemy tool, which is called "marketplace insight" which have a list of promising topics. Make course on them --- but only if you are expert on them 🙂 low quality courses seldom sell
Best of luck Cobra!