Modern C++ is not that huge, it just has lots and lots of weird corner cases and gotchas due to backwards compatibility. You can get reasonably proficient in a couple of weeks, just like any other programming language. You'll just be left with the nagging feeling that you don't understand _everything_ that might happen in your code.

Is it exception safe? Are my iterators always valid? Is this undefined behaviour?

So better keep a copy of the C++ standard open and keep reading whenever you feel unsure.