personally I'd do C, it's probably one of the most widely used - but it's difficult... Java is also a good choice but also difficult and very differently structured to something like python. To be honest, it's based on your choice. If you want a beginner language, python is most certainly the best way to start. If you want a head start on your course, C or Java is better as they teach that later into the years, but much harder like I said
I say personally I'd do C++, but that's cause I have prior experience - python is most beginner-friendly