In my opinion if you read a good C++ book (like "The C++ Programming Language", "(More) Effective C++" or "Exceptional C++").
You will not only learn good practices but should also get sense of how to write code.
Of course the samples in these Books are mostly artifical. If you read 'real-world-applications' you will always encounter pieces of code which are pretty ugly, but sometimes there wasn't just a nice clean solution for it (or a not-so-clean solution was just more efficient in terms of speed).
So I don't know if it's best to start with real applications since they can also be very overwhelming due to the amount of codesize and complexity, whereas sample codes in Books are compact and clearly laid-out.
I think for starters you would be best off reading such references as the books I have listed.
If you have to be flexible at some point in the future and have to produce ugly code, you will at least know that it's ugly code and not mistake it for "that's how it should be" ;)
