Lets see the easiest way to stream anything from the chrome internet browser. It might be video, picture and audio. follow the steps to know how to use the chromecast on pc and laptop.
First go to the chrome browser then install the google chrome extension from chrome web store.
Select the google cast icon, choose your chromecast from the given options.
You can cast from another tab also at any time from the cast extension and select this tab and close the old tab.
It is also possible to stream a stored video file just by dragging that file on the chrome tab.