When you install Wordpress, it's pretty clear how to get started: in the left menu bar of the admin interface, you can choose between posts and pages, you can manage media, links, and comments, and you can choose to edit the appearance. When you install Drupal, you find yourself staring at a welcome page that suggests you:
- Configure your website
- Enable additional functionality
- Customize your website design
- Start posting content
with some inline internal and external links that might be of some use in accomplishing those things.