Downloaded Outlook plugin does the premium come with it or do I add it on
if I add it on will I get the new features...
the Todoist for Outlook plugin is free for everyone and contains either limited functionality if you're using a free Todoist account or the full Premium functionality if you have a Premium account.
Just as the Todoist web-app, it will recognize your account status when you log in. Note - if you upgrade your account to Premium, you won't even need to reinstall the plugin.