Okay I want to build a program but I do not want the program to be copyrighted by Microsoft or any other companies. If I use one of their programs then I assume they have control over it and how it is distributed. I read that no one owns c++ but companies sell software of c++ so how do I code without getting caught in the tangled copyright web?

I don't quite understand what you mean. The full and express editions of Visual Studio permit commercial usage. You won't get "caught in the tangled copyright web" unless you're using a compiler with some special education license, and even then there's usually a way to upgrade it to a full version.

Okay lets say in theory someone built an Operating System with c++ from software they bought from a big company like Microsoft. Could Microsoft somehow claim ownership of the OS?

Microsoft does not own the code you write simply because you used their tool to write it. You are under the wrong perception.

Microsoft does not own the code you write simply because you used their tool to write it. You are under the wrong perception.

Thank you I will now start working on my project I did not want anyone to have the rights to it and wanted to make sure.