Show hidden fields on 'thank you' page of autoresponder mail

It it possible to show hidden fields by conditions only after submission on the page or responder mail and not direct on the form?

I have different questions and every time a "Yes" is answered i want to display a extra text field but after only after submission and not on the form itself.

Because there are many different questions i can't do it with "CHANGE “THANK YOU” PAGE",  or i have to make more than 20 different thank you pages for all combinations.
I prefer also to do it in a autorespond mail, but is it possible at all?

Yes, you can actually accomplish this by setting the value of the hidden field into the email template that you are going to send.

I attached the images showing how to create an autoresponder email with the form fields that you want to show:

As you can actually see, you can place the form fields that you wish on your email content. Same goes when you create a Thank You page. These two links will really help you out with your form: Setting Up an Autoresponder Email https://www.jotform.com/help/26-Setting-Up-an-Autoresponder-Email and Setting Up the Thank You page https://www.jotform.com/help/211-Setting-Up-the-Thank-You-Page

Let me know if you need more help

If the hidden field is filled, it will show in the autoresponder if you add it through the form fields feature as @carlosmdams  explained above. 

So all you need to do, is create your conditions based on the input, every time a yes is selected, populate a certain hidden field with the data that you want to show, and make sure the hidden field is selected in your autoresponder email, that way, whenever the condition is matched, it will show the hidden field in your autoresponder. Otherwise, if the field doesn't have any data in it, it will not show. 

To make this more clear, I have created this sample form, and set a condition that if yes is selected, then add "This value is hidden" into a hidden field. When i click submit, the hidden field was there in my submission report:

Please refer to this link to customize your autoresponder:

Setting Up an Autoresponder Email