>whats the best software to start coding in C++?
The basic two tools that you will need are an editor and a compiler. An editor could be something as simple as Notepad.exe, however, it's recommended you get something a bit more advanced than that. A compiler is a program that turns your C++ code into machine code, something that your computer can understand.
IDEs combine an editor and a compiler into one nicely-packaged application, so those are usually the easiest for beginners to start learning with. As far as free ones go, try something like Dev-C++ or Visual Studio Express. A popular alternative to Dev-C++ is Code::Blocks, which is slightly more current. However, your teacher will probably instruct you to download a specific IDE, so don't worry about it too much.
>I noticed my college use NetBeans which is an IDE which may be a start?
That's for Java. An entirely different programming language.