Control application using arduino

Hi,
I am working on a small project and I wanted to know, can I open an application (chrome or word) by using a arduino mega i.e, can an arduino mega send a signal serially through the usb to the laptop(Windows10) and open an application.

Thanks

You would need an application running on the laptop which receives the serial communication and then opens the other application.

An alternative would be to use one of the boards that can do keyboard emulation (Leonardo, Micro, Zero, MKR) and have it send a keyboard shortcut that opens the application. You can associate keyboard shortcuts with any program shortcut in Windows. Just right click on the shortcut, select "Properties", then enter your preferred shortcut key in the "Shortcut key" field.