How do you plan to solve it?
Use a potentiometer on analog port A0 . vary the pot and read the voltage and dispaly it on serial monitor

/*Paste your code here*/
void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);
}
void loop() {
  int signal;
  // put your main code here, to run repeatedly:
  signal=analogRead(0);
  Serial.println(signal);
  delay(50);
}
 Add video of output (know more)
Add a photo of your hardware showing the output.

