Your device may have one, two or three cameras on its back. Silver B&W Camera has setting to select a camera. We call this selecting the lens to use when taking a photo or shooting video.
Lens (camera) is selected by button shown in the picture below. If your device has only one camera then the lens selection button is not visible.
There is one extra lens listed in the selection. That is lens A – automatic. A is default and lets the operating system to choose lens to be used based on zoom and focus.
All devices have wide lens. That is selected by button W. If you device has only one camera then this is it.
Some devices have tele lens. That is selected by button T. Tele gives narrower field of view compared to wide lens.
Some devices may have third camera that is called Ultra Wide. That is selected by button UW. It gives a really wide field of view and can produce exiting results.
On front of your device you have one single camera to take selfies. Switch to it using button marked with circling arrows.