Is possible to have an external connection? (iFrame with parameter or insert a Javascript)

Hi, how are you?

I want to show a particular thing based on the value in a field (e-mail or other textbox or combobox, etc.).

I'm trying with iFrame but if I enter a parameter in the URL it doesn't work. Is there a manner to do this?

I'm trying with conditions too, but nothing.

Or is possible to insert a javascript button that do anything? Something like a funcione, write in a box o anything else.

Unfortunately, it is not possible to insert JavaScript code due to security purposes. What you are trying to accomplish is not possible. You can only forward data from one form to another form upon submitting the form: https://www.jotform.com/help/351-How-to-Automatically-Pass-Form-Data-to-Another-Form 

Open a new thread if you need anything else, we will be glad to assist you.