Arduino wait for incomming data from blynk terminal

Question

I need to add wait command in code where it waits the next input value from blynk terminal to arduino? How can I do that? please help, I will appreciate your help, Thank you.

Here is my code

BLYNK_WRITE(V0)
{
 String i = param.asStr(); //String Value from blynk

  if(i == "A"){
      Serial.println("Ready to enroll a fingerprint!");
      Serial.println("Please type in the ID # (from 1 to 127) you want to save this finger as...");

      Blynk.virtualWrite(V0, "Ready to enroll a fingerprint!");
      Blynk.virtualWrite(V0, "Please type in the ID # (from 1 to 127) you want to save this finger");


int numb = i.parseInt; //I need to add a command here to wait for the next blynk terminal value
Serial.print("Enrolling ID #");
  Serial.print(numb);
}}