I need to deactivate several PCs on my account and there is no commands tab. How do I change this?

Hello ?,
 
Welcome to the Webroot Community,

Is there more than one user profile (Online Account) set up under your Key Code? I suspect that the profile you are signing in under may not be set for Admin access. Once you log into the Account Console, are you able to click on the email address at the upper right hand corner and choose Manage Users from the drop down? 
 
Follow below and click on your user name in the top right hand corner and from the dropdown select 'Account Settings' and at the bottom of the page displayed you should see something like this:
 

 
 
If it does not say 'Admin' then click on 'Change' and you should see something similar to the following:
 

Click on the down arrow on the right (arrowed above) and select 'Admin' from the dropdown options...then click on Save Access & Permissions...
 
Hope this helps?