If your Brother printer offline Windows 10 and you want to verify if your Brother printer is On then you must follow these steps:-
1. If your Brother printer’s LCD screen is blank, then try to wake it up from sleep mode.
2. Then make sure that your Brother printer’s cable is plugged into a fine socket and also make sure that the power is on.
3. Inspect the LCD screen of your Brother printer for any error messages such as Paper Jam or Toner empty.