Display custom message after submitting a Google Form

There is no way to add a custom confirmation message for the current user of the currently open Form. You can run code to change the confirmation message when the Form is submitted, but changing the confirmation message when the Form is submitted won't take affect until the NEXT Form is opened, and that's too late. So the next person to open the Form would get the confirmation message of the previous user.

You would need to convert everything to a stand alone HTML App for something like that.

Google just released a new version of Google Forms. In the settings you can change the confirmation page message for respondents. You can save a link to a web page in the custom message. So if you can create a web page with the data you want displayed, you should be able to save the link in the custom message.

In order to achieve the above-mentioned goal, you need to get the Google form on your web page. No, I am not talking about embedding the form to your web page but to create a stand alone HTML page. The reason behind doing so is since Google is a third party website, editing any code in Google forms is not possible and there is no other way (at least I could not figure out Yet) to place custom thank you page URL for the Google Form. You can even remove certain codes in your HTML page to make sure it doesn't look like or says Google form. Basically, to have custom URL you need to replace

Code to be replaced for custom Thank you url in Google form

In case you are not a techie, Playing with codes might break the code.This step by step blog for customising Google form might help you.