Hello,

if it is the same contact form as the one being used in the Contact page

http://clapat-themes.com/wordpress/harington/contact/

you can add it as shortcode/block/widget anywhere with Gutenberg or Elementor

https://blog.cf7skins.com/contact-form-7-selector-block-for-gutenberg-block-editor/

Regarding the questionnaire you may want to use a plugin for this. Be mindful that it may now work with ajax  page transitions enabled. 

We cannot guarantee any of the third party elements working w/ AJAX because CSS styles are usually loaded in the header of the page, dynamic js effects in the footer.

When a page is loaded with ajax header and footer stay the same (the original starting page), the content is loaded in an inner container.

You can disable ajax in customizer -> general settings. You can also keep the ajax on and add the page containing the elements as custom menu link therefore bypassing ajax.