Gist for https://github.com/codearryaas/wp-react-theme functions.

functions.php

<?php
/**
 * Js & Css assets for child theme.
 */
function twentynineteen_child_assets() {
	wp_enqueue_style( 'twentynineteen-style', get_template_directory_uri() . '/style.css' );
	if ( ! is_front_page() ) {
		return;
	}
	wp_enqueue_style( 'twentynineteen-child-style', get_stylesheet_directory_uri() . '/style.css' );
	wp_enqueue_script( 'twentynineteen-script-name', get_stylesheet_directory_uri() . '/assets/js/dist/bundle.js', array(), '1.0.0', true );

}

add_action( 'wp_enqueue_scripts', 'twentynineteen_child_assets' );

// More to come.