Ask HN: What are the most useful AI/ML courses I can do online?

So I'm a geography and computing graduate working in mapping and spatial analysis for about the last 7 years. It's a fun field that explores society and technology at a natural intersection. I'd like to do an online course that is AI/ML related, it seems to be the buzz in my field and would like to explore it more. If nothing else it will help with promotion and going up the pay ladder. I also like it and found the basics of it interesting while in university, although I've forgot a lot of it. I've noticed a myriad of courses online but haven't had any recommendations about which are high quality interesting courses. I'll happily pay so not restricted to free courses. I feel if I can at least explore the field I'll get a handle on if it's something i'd like to spend more time on.