Step 1:

bread board

LED( different colour)

220E resistors

Arduino UNO

HC-05 bluetooth module

male-female connecting wires

male-male connecting wires

android smartphone

Step 2: Schematic

tinker cad simulation

Step 3:

connections

Step 4:

code:

Step 5:

install mobile application arduino voice vontrol

Step 6:

connect bluetooth

Step 7:

try saying all to open all leds

try saying switch off all to switch off all leds

try saying living room on to open red led

try saying switch off living room to switch off red led

try saying kitchen to open white led

try saying switch off kitchen toswitch off white led

try saying study room to open green led

try saying switch off study room to switch off green led

try saying fan to open yellow led

try saying switch off fan to switch off yellow led

try saying room to open green blue

try saying switch off room to switch off blue led