I think python is generally used for AI and data science stuff, so you'd probably be better off learning that.

That said, I think one of the best ways to learn how to do something is dive right into it. I'm currently in the process of writing a deep learning library in C: https://github.com/siekmanj/sieknet

So if you're dead set on C++, I'd say the best way is to try to build something cool right off the bat.