iFrame problem

Hello there coders! I am iframing part of a website into my own site. The part that is iframed has submission form and when a visitor fills out the form, there is a popup that appears, however due to the iframe size, the visitor cannot see the whole popup. I need a solution that will make the popup appear entirely and that will redirects the visitor to the "thank you" page. To make it easier to understand, I have posted the content of my page and a read me file in this project request. Thanks and happy bidding!