Please note that installation and customization services are beyond the support process, however I will try to help you as much as I can 🙂
The demo front page is built using the following tools:
– SeoWP theme, with a child theme. This is a great, high perfromance theme and it includes a live page editor as well: https://themeforest.net/item/seo-wp-online-marketing-seo-social-media-agency/8012838
– The front page is created with the live editor, that is included in the theme.
– Then the search shortcode is placed within a 6/12 width module block, like so: https://i.imgur.com/YilNjSO.png
You might have to practice the live editor tool, or check the documentation, it took me some time to get used to it.
– The I created the search bar, and simply placed the shortode there, also all the other elements, like the buttons, titles etc..
If you like my products, don't forget to rate them on codecanyon :)