Loading Bootstrap with wp_enqueue_style and wp_enqueue_script

Here you go..

function xobamax_resources() {
    wp_enqueue_style('bootstrap', get_template_directory_uri() . 'css/bootstrap.min.css');
    wp_enqueue_style('style', get_stylesheet_uri());
    wp_enqueue_script( 'bootstrap-js', 'https://maxcdn.bootstrapcdn.com/bootstrap/3.3.4/js/bootstrap.min.js', array('jquery'), '3.3.4', true );
}
add_action('wp_enqueue_scripts', 'xobamax_resources');

I have added the CDN version, You can replace that with your local copy. I want to suggest you to read more about wp_enqueue_script()