How to output wp_enqueue_style() in HTML head instead of footer

by

hook into init action on your initial plugin function

add_action('init', array(__CLASS__, 'your_function_within_class'));

and add the function

public static function your_function_within_class()
{
    
    wp_register_style('myfirstplugin-admin-css', '/wp-content/plugins/myfirstplugin/assets/style.css', false);
    
    wp_enqueue_style('myfirstplugin-admin-css');
}

hope this help