make existing website more user-friendly

Hi, a simple website with PHP allows completing a form and once all fields contain valid data saves it into a MySql DataBase. Some of the data is completed manually and other fields are copied from the iframe and pasted into the main page. But there are many fields so it´s not handy. I need an implemented solution to acomplish the same but more user-friendly. some of the fields will still be filled in manually but the data of some other fields need to be extracted from a iframe itself. about the website in the iframe, the user has to login and access his personal data, once the desired content is displayed within the iframe it has to be copied into the fields of the main page. the content to be coppied is text. IMPORTANT: the iframe and main page are not in the same domain. The solution might require bypass same-origin policy, I don´t think scrapping applies because the user has to login, view his own data and then load it into the form. The website is already implemented, and works with the database. Just the described solution is necessary to make it more user-friendly. Attached file. Best regards.