Create WordPress Child Theme

You can quickly create a WordPress child theme by creating a new theme directory and adding these two files.

style.css

/*
 * Theme Name: My Child Theme
 * Template: twentynineteen
 */

Where the Template value is the directory name of the parent theme (in this case, we’re making a child theme of Twenty Nineteen, which is found in the twentynineteen directory).

functions.php

<?php
/**
 * Child theme functions.php
 *
 * @author Sal Ferrarello
 * @package salcode/childTheme
 */

add_action( 'wp_enqueue_scripts', 'fe_enqueue_parent_theme_style' );

/**
 * Enqueue parent theme style
 *
 * @author Sal Ferrarello
 */
function fe_enqueue_parent_theme_style() {
    wp_enqueue_style(
        'parent-theme-style',
        get_template_directory_uri() . '/style.css',
        array(), // Dependencies.
        '0.1.0', // Version.
        'all'    // Media.
    );
}

Official Child Theme Documentation

See the WordPress Official Child Theme Documentation