Customize & squeeze a landing page

- Add submit form in the landing page to collect data from users ( Name, Email, Phone ). - Form should pass the collected data to Google sheet. - In the submit form ( Phone input field ) I would like this field to add the country code and display the country flag based on the user country automatically. Note: I can pass user country code in a parameter in the landing page URL, then you can detect it from the parameter and display the country code and flag based on that - Landing page loading time should be less than a second - Add Google Font to the page - Redirect the page after submitting form to Thank you Page - I would like to be able to pass parameters from Landing Page to Thank You Page - Clean the landing page from all unnecessary code to make it load in less than a second