how to add js scripts to wp sites. Create a js directory in the theme directory then add this to functions.php for the theme
<?php
function site_functions_js() {
wp_enqueue_script(
'site_functions',
get_template_directory_uri() . '/js/functions.js',
array('jquery')
);
}
add_action('wp_enqueue_scripts', 'site_functions_js');
?>