My recommendation is to first read Scott Meyer's book "Effective Modern C++". This will give you a tour of the language features in modern C++ without wasting your time teaching you the basics, which are going to come back to you rather quickly anyway. It's a short book and it's not going to cover everything you need to know in modern C++, but you can read it quickly and after you've read it and done a little C++ programming you'll know which things you want to dive into further.
As for what kind of programs to write to get excited about C++, I personally feel like systems programming is the area where C++ really shines, and I would encourage you to find some kind of project in this area that excites you. For example, write a simple high-performance key-value database using mmap. Write a httpd using boost::asio or even just using epoll directly. Something like this. There are a million projects to choose from, just pick something that you find interesting.
With regard to CUDA, while it is true that it's an area where people use C++ today it's also fairly different from writing regular C++ programs since you need to use different tooling and the programming paradigm is a little different. If you're really passionate about CUDA I don't see any reason why you couldn't start there, but I think it would be easier to do regular userspace C++ programming first and then transition into CUDA later if you are interested in it.