The last time I learned a new language, I was at the beginning on my PhD, and the language was Python. And C++ actually (i.e. proper C++). Since them, these two languages have evolved a lot and it can be a challenge to find good books covering the latest aspects of these languages.
But once again, this is a very good book on the language itself. I still have to read several of the most advanced concepts, like Promises, or the way multiple inheritance is done, or properties. But I know where to look if I need to use these concepts. I have a good grasp (I hope?) of date and time (although I got bit my some odd behavior of the Date class, I suspect I will always work by transferring strings or seconds since epoch!), I change my way of thinking from a pure imperative or object-oriented point of view to add more functional callback style programming. I don’t think I would have been able to dive directly into a client-side framework book without this preliminary knowledge.
The book on its own is not enough to write client-side or server-side code. You can implement functionalities based on code that is already existing, but with just the book, you will be stuck to write anything of value.
Still, it covers all the common point between server- and client-side applications. After this read, you can dive into a book on either aspect, depending on your requirements.