Sure. In the Form Editor, click the Thank You page icon and select the second radio button: Redirect to a web page. Paste the URL in the box below and your submitters will be redirected there.
By default, the selected button is Show text; this is for showing a confirmation/thank you message after submission. If you want to both show a message and redirect to a web page, select the third radio button: Show text, then redirect to a web page. Type in the confirmation message and paste the URL of your web page in the box below.
You can select from the dropdown list the way the webpage will open, in the default frame, in the same frame, in the parent frame, or in new frame (if browser allows it). Use the option that suits your needs best.