I know a bit of C (for programming arduinos), and that’s not too hard to pick in the context of arduino.
I have a bit of Python, which is a good place to start general programming. I have a couple of useful little programmes to help me with work and my home shopping list.
I like R a lot for statistics, especially for making beautiful graphs with ggplot2.
I don’t they’re particularly hard to pick up, but if you don’t use them regularly you have to relearn to use them (that happens to me a lot). I’d especially recommend trying to learn it in a class to begin with, it can be handy to have someone to ask questions, especially when you get frustrated and have no idea why something’s not working