You've taken your first step into a larger world.
1. Launch the compositor.
2. Click on Camera in the left tab to open up the camera page.
3. Click on the Add Camera icon to create a new camera profile.
4. In Type, select Video Camera, Kinect or iOS (NDI).
5. In Device, select your Camera Device or Capture Card.
6. In Mode, select your desired resolution and frame rate.
7. Name your profile and Save it.