how to add thank you note after submission then direct to another website

You can create a custom thank you message and then add the other site link:

http://www.jotform.com/help/211-Setting-Up-the-Thank-You-Page 

Or you can create an external thank you page (as we don't allow the use of JavaScript for security reasons) and add a redirect script:

http://www.jotform.com/help/89-Create-a-Custom-Thank-you-page-with-Auto-redirect 

If you need assistance implementing these solutions please let us know and we'll be glad to assist you.