To display the selectors above the search bar, I suggest using the settings shortcode. It basically allows you to display the settings box above the search bar. In your case the post/page with both shortcodes would look like:
[wpdreams_asp_settings id=1 element='div'] [wpdreams_ajaxsearchpro id=1]
The plugins main feature is a search bar, thus a search phrase is required, however there is a knowledge base article to make it work without any phrases: https://wp-dreams.com/knowledge-base/how-to-use-filters-only-and-hide-the-search-bar/
Just skip the Custom CSS part of that tutorial, since you want to display the search bar.
It does not matter how many restaurants you have, by default always 10 is displayed (its the results limit by default). You can of course increase that to a higher number if you want to on the General Options -> Behavior panel: https://i.imgur.com/9nDaAC0.pngBest,
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