PWM Code to for mosfet gate

Projects General Guidance
22 
int pwmpin_1 = 9;
int pwmpin_2= 10;
int pot = A0;
void setup()
{

//  change pwm frequency of pwm pin 9 and 10 .....from 490 Hz to 32kHz
 TCCR1B = TCCR1B & B11111000 | B00000001;
 
  pinMode(pwmpin_1,OUTPUT);
  pinMode(pwmpin_2,OUTPUT);
  pinMode(pot, INPUT);
   
}
void loop()
{
  int potVal = map(analogRead(pot), 0, 1023, 0, 255);
  analogWrite(pwmpin_1,potVal);
  analogWrite(pwmpin_2,potVal);
}

that is my last code which generates 30Khz well and i am controlling the duty cycle with POT
i need to add Phase shift between the 2 Pulses but i can't figure out how