Script and CSS Call in function.php

 /*  CSS*/
 * Enqueue styles
 */
if ( ! function_exists( 'awaiken_load_styles' ) ) {
function awaiken_load_styles() {

wp_enqueue_style( 'bootstrap', get_stylesheet_directory_uri() .'/css/bootstrap.min.css', false, null );
wp_enqueue_style( 'owl_carousel', get_stylesheet_directory_uri() .'/css/owl.carousel.min.css', false, null );
}
}
add_action( 'wp_enqueue_scripts', 'awaiken_load_styles' );


/* JS  (function.php) *
 * Enqueue script
 */
if ( ! function_exists( 'awaiken_load_scripts' ) ) {
function awaiken_load_scripts() {

wp_enqueue_script( 'bootstrap', get_stylesheet_directory_uri() . '/js/bootstrap.min.js', array( 'jquery' ), '', true );
wp_enqueue_script( 'owl_js', get_stylesheet_directory_uri() . '/js/owl.carousel.min.js', array( 'jquery' ), '', true );
wp_enqueue_script( 'function-js', get_stylesheet_directory_uri() . '/js/function.js',  array( 'jquery' ), rand(), true );
}
}
add_action( 'wp_enqueue_scripts', 'awaiken_load_scripts' ,1000);

/* function.js file setup */

(function ($) {

    "use strict";

var $window = $(window); 

var $body = $('body'); 

/* codeing */

})(jQuery);