@jitu059_Lalat The long and short if it are, you have two ways to do this:
Find all the dll's that your app depends on. You can do this with the tool http://www.dependencywalker.com/. Once you found all the dll's copy them into the same folder as your executable. This is now your "delivery package" you will copy the executable + dlls from PC to PC. This method is perhaps a bit easier/faster in the short term, but when you compile with different versions of Qt/Windows you may require a different set of dlls (i.e. Qt4 Dlls don't match Qt5 Dlls).
Download the Qt source code and compile it for static linking. Then when you build your code you will get a much larger executable file, but it will contain everything it needs - a standalone executable. This is perhaps a bit more work on your part, but master this and it makes deploying your project from PC to PC much easier.
Have a go at one or other method, if you get stuck then ask again. But as SGaist said, there is lots of documentation out there already : )