So, if you're simply looking to convert the knowledge you already have, web searches like
C++ for C developers
C++ for python developers
... will get you up to speed.
As a relative beginner, you'll also learn features of the original languages that you didn't know, and get a taste of what sorts of features professional developers find helpful and worthy of discussion. Comparing languages like this is an excellent way of expanding your knowledge of programming languages as a field!
If I were you, I'd also consider searches based on the languages you say you are already familiar with:
C for python developers
Python for C developers
... and so on.
You can find out quite a bit about programming languages as a field by working through these comparisons in languages that you already know.
That's my answer to the question you've directly asked. Before I go, though, I do have one important caveat: your goal shouldn't be to "learn" as many languages as possible. Your goal right now should be to find a home base language that excites you enough that you want to delve deeply into it. Depth is far more valuable than breadth, if only because picking up a new language is relatively easy (as demonstrated by my searches). Honestly, as long as the languages share similar paradigms1, you can translate most of your knowledge of one language to another in roughly an afternoon.
So, by all means go and check out C++! But when you've explored around a little, see if it also ignites your sense of fun and intrigue. If it does, then really take some time to start to learn the language in depth. You might spend a year, maybe a few years, or maybe only a few months before you lose interest. But the goal is to dive deep, and really learn something well. As strange as it sounds, deep diving will ultimately give you a lot more flexibility than more shallow explorations as you learn and develop.
1 - When they don't share paradigms, such as moving from procedural to functional programming, then things become much more interesting, and the process of learning the language is much tougher, though the rewards are also much greater.