On the right side of the Signon window are a number of buttons for managing your ODBC Datasources. Many of these are only visible when you have selected Show all, rather than Show recent.
These ODBC Admin functions can be hidden with Options > User Rights > Hide ODBC Admin functions on Signon window.
Note that your ODBC Datasources are in two categories:
You can only create / configure / delete System Datasources if you have sufficient rights on your PC.
For more information on configuring your ODBC Datasources, see Configuring a Database Connection.