For realtime sound synthesis/audio programming there is no way around C/C++. Other (high level) programming languages won’t give you that kind of lowlevel control that it necessary in that area.
And, as also already suggested, the Juce Framework is an excellent base which is used in a vast number of professional audio programs.
But I wonder if an absolute beginner in both areas (programming and audio/synthesis stuff) should really start like this. Simply just learning C/C++ can be a quite frustrating experience …
Maybe starting with Max, SuperCollider or Pure Data and spice that up later on with some own extensions coded in C/C++ is the better way.
And when it comes down to hardware to run own patches on Organelle is also a nice option (runs Pure Data patches).