C++ Program:

Example:

#include <iostream>
using namespace std;

int main() {
  int num;
  cout<<"Enter a number :";
  cin>>num;
  cout<<"You entered : "<<num;
  return 0;
}

Output:

  Enter a number : 121
  You entered : 121

cin>>variableName;  //to take user input
cout<<variableName;  //to print variable

To take input, use cin>> to store your input inside a variable and

to show the variable in the output screen just use cout<< (type variableName after it)