Thunderbird - 4 ways to to get the account settings
  
Method 1
 
Right click once on the account name in the left column.
In the drop down menu click on 
Settings...
   
  
Method 2
 
In the left column, click once on the account name to select it.
Then click on the 
View settings for this account in the right-side pane.
  
 
  
  
Method 3
  
 
Click on the "menu button" 

, go to 
Options / 
Account Settings...
   
  
  
Method 4
  
 
Click on 
Tools / 
Account Settings...
If "Tools" or "Menu Bar" isn't there, you can hit the 
ALT button or 
ALT+T on your keyboard.