I didn't know what this was, so I took the time to Google it...Udemy being a learning platform and place to buy courses. I wouldn't knock you for taking a course, but would it really be money well spent? If you think of the essential things you want to know from a particular category. Can you simply do enough reading, networking and so on to get the job done?
Not to say its wasteful, some people benefit from one. just my take on it when I hear about people buying into one. Often, the information is already out there on the net (and free)