I just went through OnlineCourseing to find an online course that teaches C++. I found Udacity could be a good option. I am planning to enroll in it. Any suggestion?
With C++ you wont come far in Unity as it uses C# as scripting language (and this is a Unity forum!). So I would suggest to either search for a C++ forum or search for a C# course if you want to use Unity. Or what is it exactly what you want to achieve?