hello, can somebody please explain what is the main difference between visual studio and Qt, thanks in advance
Visual Studio is an IDE, a piece of software that combines a text editor and other programming facilities (integrates a compiler, testing suite and more). This is where you write you code and debug it.
QT is a library - it is a library of software intended to be used by programmers to build up on. You can use it when writing code, by writing code for and with it.
You can use Visual Studio to type in and write applications with the QT library, but not the other way around.
You could create an IDE using a library such as QT - Visual Studio is using WPF as its graphics library. You would still write the IDE with an editor first...
Are you talking about Qt Creator? That is an IDE, like Visual Studio, but is optimised for creating Qt programs. If you're using Qt a lot then use Qt Creator.