Using jquery with wordpress using wp_enqueue_scripts

It sounds like your template is missing a call to wp_head() which will output your enqueued scripts and styles. You’d normally place wp_head() in your header.php template and include this in your page template.

To conditionally enqueue jQuery based on the page template being used you could use the following code:

add_action( 'wp_enqueue_scripts', 'custom_theme_load_scripts' );
function custom_theme_load_scripts() { 
    if ( is_page_template( 'page-template.php' ) ) {
        wp_enqueue_script( 'jquery' );
    }   
}

Keep in mind that plugins may require jQuery and therefore enqueue it on other pages/templates.