Very simple child theme functions.php

functions.php

<?php

class ChildTheme {
  
    /**
     *
     */
    public function __construct() {
       $this->load_hooks();
    }

    /**
     * add action hooks and filters 
     */
    public function load_hooks() {
      add_action( 'wp_enqueue_scripts', array( __CLASS__ , 'enqueue_styles_scripts' ) );
    }
  
    /**
     *  enqueue scripts and styles
     */
    function enqueue_styles_scripts() {
      /* enqueue parent style */
      wp_enqueue_style( 'parent-style', get_template_directory_uri().'/style.css' );
    }
}


new ChildTheme;