Does drush support everything I can do with web admin interface?
No, you can't. That's not possible.

Every command needs to be explicitly provided to Drush. Many contrib modules now come with integrated drush commands, for example Devel generate, Features, Views, XML Sitemap and so on.

To see the list of commands that are available to you, call drush help. You can get detailed help on each command with drush help &lt;command&gt;.