changing the head light patterns with PWM duty cycles

helo electro tech
I am working with the LED lights
i arranged the LEds in a arc with 3 rows and 5 LEDs in each row
i want to shift the light patterns to 5 degrees to the right then again 5 degrees to right so on
and same i want shift the pattern toleft also .
i want to achieve this with the PWM input to the LED lights but i am not understanding how can i shift the patterns and what are the required PWM duty cycle input will give to shift patterns
help me

Use a Shift Register.

i am not understood sir ,
basically i want to know the relation Between PWM duty cycle and the amount of light pattern can shift

I don't understand your description.

As I understand it, you have a 3 x 5 matrix of LEDs.

You can use a PWM signal to set the LED brightness.

I don't understand what you mean by "I want to shift the light patterns to 5 degrees to the right then again 5 degrees to right so on"

Please draw a diagram that shows what you want to do.

PWM will control the brightness, not the light pattern (unless you switch off rows/columns of LEDs).