Wordpress shortcode in 2 minutes

my_first_shortcode.php

<?php
/**
 * Plugin Name: Sample Plugin
 * Plugin URI: https://wpedmunds.uk
 * Description: A demo plugin
 * Version: 1.0
 * Author: WP Edmunds
 * Author URI: https://wpedmunds.uk
 */



function my_shortcode($atts = []) {

	$html = '
		<h1>Hello World!</h1>
	';

   return $html;
}



function my_shortcode_scripts() {
  wp_enqueue_script('jquery');
}

add_action('wp_enqueue_scripts', 'my_shortcode_scripts'); 
add_shortcode( 'MY_SHORT_CODE', 'my_shortcode' );