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The image in the picture is not a phone, but shows the underside of Apple's Magic Mouse. The image is graphically indicating to the user to turn on the Bluetooth mouse that is paired with the Mac, if it is off. If you see this graphic, it means that the Mac is not detecting the presence of a mouse, whether a wired USB mouse or a wireless Bluetooth one.
It's telling you how to turn on a wireless mouse. Do you have a mouse attached to the Mac? – Gordon Davisson – 2018-07-30T16:49:55.943