Copy application files to Boot to Qt devices
Specify settings for deploying applications to Boot to Qt devices in the project configuration file and in Projects > Deploy Settings.

The deployment process is described in more detail in Deploy applications to remote Linux devices.
Launch applications on boot
To have your application launch on boot, select Add Deploy Step > Change default application > Set this application to start by default.
See also How to: Build and Run, How to: Develop for Boot to Qt, and Developing for Boot to Qt devices.