These headsets plug into your device (iPad, Chromebook or MacBook) and are used as headphones and a microphone.
The sound coming in to the headphones would be considered 'output' from your device, and the sound coming in to the device from the microphone would be the 'input'. You may need to adjust these volumes/levels in the settings.
There is a volume knob on the cord, so please adjust the volume on your device AND on the headset to your preferred level.