I would say that you are right, in fact you didn't learn only a language (AS3), you learned imperative programming. which in any language of this paradigm, will break down to the exact same things and concepts (loops, ifs, functions..). Why, because the CPU is doing so.
There are other paradigms, like functional programming (lisp..), and logical programming (prolog..). Both have different way of thinking the program design/execution flow.
But indeed, knowing AS3 made you know C++, somehow. Of course, while this is true, it is also false because after the paradigm, there is all the rest: software engineering. And that one, is the big one. It takes a few weeks to master the imperative programming paradigm, it takes a few decades to master software engineering.
C++ is the one language that has all, or almost everything, and is also the one language that can actually not be mastered. Even the persons writing the standard are discovering new rules, new patterns, new ideas, new smells, new pitfalls, new must-not-do, on a monthly basis... and it is a real never ending live feed to learn programming (in C++ particularly).
So good luck on your way with that, I know I love that adventure.
GotW is a bit hard at first, I would recommend programming on yourself a bit, shooting yourself in the foot, you tend remember better things like that
After, you can go back to read the C++ faq lite and GotW as much as you want, and agree as an equal thinker to the great minds that wrote it. But going as a beginner, you will only be able to say "oh really, hmm, ok then I'll take the advice". Its funnier to have the experience to actually having come up yourself with what is said in those Faqs/GotW.
You will notice on those pedants sources, that the standard is mentioned quite a lot. It is actually a good thing to DO read it. However, the 2003 version is around 800 pages, the 2011 is around 1800 pages (or 1600?). It is a brain twister, it is like reading the civil code book. And if you are not native in english it is even more difficult.
But please, about this, take my advice : the very C++ standard paper, is a much better source than any book and tutorials/resource found on the net written by average Joe. Because more often than not, people who think they can go teach others, only learned through compiler reporting; which is a bad way, especially when that compiler is from microsoft.
If you have difficulties at planning the tasks, don't worry, it is actually full time job for many people in this world. And to do it, it requires to know what is possible, and how it is possible also, at last on a vague latent zone of your brain. You have difficulty planning things when you are too unsure about the way to do achieve it.
For example, if you want to draw a 3D rotating cube, and when you think about how to start, and you can't come up with anything, it is because you don't know how to do it yet. So you need to start draw 2D things instead, and suddenly things are getting clearer "ah yes, I know drawing a thing is drawing pictures or sprites, I know pictures because I have manipulated them in paint or so". You want to make it cross the screen "ah yes, I know I can use a loop to increment a position variable and draw at each iteration". Because you have imperative programming knowledge.
Just continue on this path and one day you'll arrive "Ah, the 3D cube, now I know i need a representation of the vertices in memory, a model matrix and a projection matrix, I need a line drawing routine, and maybe a timer to adjust the rotation speed..." etc etc
so just do like the others said, tic tac toe etc...
One last word, about SFML, it is actually a good library to start with because it has a good C++ design. If you had started with OpenGL for example, it would have taught you old C-style design.