https://angreifer.org in the USB port

angreifer.ino

// 15€ hardware: https://www.aliexpress.com/item/1005003672079080.html
// 5€ hardware: https://www.aliexpress.com/item/2040316211.html (needs rewriting with DigiKeyboard.h)

#include<Keyboard.h>
#define KEY_DELAY 50

void setup() {
  
  /*  KeyboardLayout_da_DK: Denmark
      KeyboardLayout_de_DE: Germany
      KeyboardLayout_en_US: USA
      KeyboardLayout_es_ES: Spain
      KeyboardLayout_fr_FR: France
      KeyboardLayout_it_IT: Italy
      KeyboardLayout_sv_SE: Sweden
  */

  Keyboard.begin(KeyboardLayout_sv_SE);

  // Might lose first button presses otherwise
  delay(4345);

  // Windows
  Keyboard.press(KEY_LEFT_GUI);
  Keyboard.press('r');
  delay(KEY_DELAY);
  Keyboard.releaseAll();
  
  // Linux
  Keyboard.press(KEY_LEFT_ALT);
  Keyboard.press(KEY_F2);
  delay(KEY_DELAY);
  Keyboard.releaseAll();

  // Open attack website
  delay(KEY_DELAY*5);
  Keyboard.println("https://angreifer.org");

  // Make it more menancing (F11 = Fullscreen)
  delay(2345);
  Keyboard.releaseAll();
  delay(1345);
  Keyboard.press(KEY_F11);  
  delay(KEY_DELAY);
  Keyboard.releaseAll();

  // Don't really do anything, don't even loop
  delay(230000);
}

void loop() {
  delay(1234);
}

High school friendly budget:
15€ hardware: https://www.aliexpress.com/item/1005003672079080.html
5€ hardware: https://www.aliexpress.com/item/2040316211.html (needs rewriting with DigiKeyboard.h)