The 3cx desktop app can be used in 2 different modes

1. CTI (default) - The app acts as a remote control for your desk phone

2. Softphone - The app acts as a software telephone.  You can place calls using the microphone and speakers on your computer.  It works best if you have headphones.

To make an audio or video call:

1.  Click this icon at the top of the app.  Click "Softphone" to change the mode

2. Use the numbers on your computer keyboard to dial a number.  You can also search for a contact.  Hit the enter key or click the "call" button to place the call.

3. To turn on video while on a call, press the video button.  Not that the person that you are calling must also be using the 3cx app as a softphone in order for the video to work.