HelloTeensy.c

#define TEENSY3
#ifdef TEENSY2
#include<usb_private.h>
#endif

void setup()
{
  delay(5000); //Delay required for OS to connect the device properly
  Keyboard.set_modifier(MODIFIERKEY_RIGHT_GUI); //Tell Teensy to press Windows key
  Keyboard.set_key1(KEY_R); //Tell Teensy to press R
  Keyboard.send_now(); //Press "Windows key + R"
  
  delay(500); //Wait for half second
  Keyboard.set_modifier(0); //Tell Teensy to release Windows key
  Keyboard.set_key1(0); //Tell Teensy to release R
  Keyboard.send_now(); //Release "Windows key + R"
  //Teensy should open a run prompt now
  Keyboard.print("notepad"); //Type notepad in the run prompt
  Keyboard.set_key1(KEY_ENTER); //Tell Teensy to press Enter key
  Keyboard.send_now(); //Press Enter

  Keyboard.set_key1(0); //Tell Teensy to release Enter
  Keyboard.send_now(); //Release Enter
  delay(2000); //Wait for notepad to open
  Keyboard.print("Hello World "); //Type Hello World in notepad
  delay(1000);
  Keyboard.print("This is  Msg From . ."); //Type Hello World in notepad
  delay(1000);
  Keyboard.print("Un4ckn0wl3z"); //Type Hello World in notepad
}

void loop()
{
}