You can easily customize the Thank You page by accessing the Form Editor. From the Form Configuration side menu, select the Thank You page icon.
The next step is to click the option Show HTML block. Here you can add different codding elements, images, text styles, form inputs, and videos. You can also add a form input in the HTML block. Just select the field in the dropdown list located on the top, and press the Add button on the right.
After submitting the form, your visitors will be redirected to a page with the content you have customized in the HTML block. It’s important to mention that the form’s header will also appear on the Thank You page.
If interested in how to embed videos in the HTML block, follow the steps from this documentation. In short, just hit Source code in the HTML block and paste the embed code there.
Are you familiar with editing notification email templates in HTML mode for your online forms? If so, then the HTML block of the Thank You page is not that different. The content within the HTML block is displayed the same way within the layout of the Thank You page. The only significant difference is the form field, because here you see a code of the field, while on the Thank You page your form visitors will see their input.
Try out the options of the HTML block and see how the content is displayed after submission.