ketanco wrote:ok so I would install raspbian OS to my laptop and run that OS, and with that use a programming language like Phyton or C to start programming? is that correct?
You install Raspbian on the Raspberry Pi, not on your laptop (though technically you could do that as well).
ketanco wrote:when I run raspbian OS, does it mean my laptop will be running on that OS instead of windows,
No, Raspbian runs on the Pi. There is absolutely no need to touch anything on your laptop.
Raspbian is an alternative to Windows - they are both an "OS" (an Operating System). Most people choose to run Raspbian on the Pi.
Raspbian is a form of Linux. One advantage of that is that its free! Another is that it has great support for programming built in. As people have said, it comes with several important and extremely widely used programming languages already included. No need to install anything - just start programming!