What I actually want to do is to view different files of some project on different screens. If they are in different windows, I can easily drag one window to another screen.
It's fine if there are other ways I can do this.
You can drag the editor tab to another screen and it will open in a separate window. See the Detaching Editor Tabs help section for details.
Shift+F4 does the same:
The shortcut can be changed here: