It is possible to run a customized Javascript on the survey page as per your requirement. For example, to execute a specific action like auto redirection to your Website after the user completes the survey. 

To do this, follow the below steps:

1) Click on the edit survey option from delivery manager.

2) Edit the last page of the survey.

3) Click on "Add a widget" drop down and select the Javascript widget.

4) Add below code as shown in the Javascript widget and save the survey.

The code below will redirect the user to "" 5 seconds after the user completes the survey.

setTimeout(function() {
 window.location.href = "";
}, 5000);

For more information about editing a survey, visit this page