I can't increase the volume of my tv and decrease it

I can't increase the volume of my tv and decrease it

My tv can’t be increased and decreased by volume,and there is something under the screen headphone 0 which means it suppose to be 100 i.e increase and decreasing with the use of remote control and when you go to settings then you scroll to sound then you click ok it can’t go to the otherside i.e the audio display.so pls help me fix it

ANSWERS: