When you install the Qt SDK, the build and run settings for the tool chains delivered with the Qt SDK are set up automatically.
To view and modify the settings for currently open projects, switch to the Projects mode by pressing Ctrl+5.

You can add a target if the development environment for the target platform is installed on the development PC and the Qt version is configured. Click
and select from a list of available targets. To remove a target, select it and click
.
You can select the targets and use the Build menu commands to build, deploy, and run projects.
The project pane consists of the following tabs:
Use the Build and Run buttons to switch between the build and run settings for the active project.
If you have multiple projects open in Qt Creator, use the tabs at the top of the window to navigate between their settings.