Spotlight is included with every license, Core and PRO alike.
Turn it on:
Go to Settings, find Spotlight Search, and tick Enable the Ctrl+K / Cmd+K spotlight overlay.
What it does:
On any page of your site, a visitor presses Ctrl+K, or Cmd+K on a Mac, and a search overlay opens in the middle of the screen, already focused. They type, they get instant results, they press Escape to close. No shortcut needed on your part, and no shortcode to place.
Taking over your theme's search box:
Tick the second option and clicking your theme's own search field opens the spotlight instead. That is the fastest way to upgrade a theme's built in search without touching a template.
The placeholder:
Set your own prompt text so it fits your site, for example Search everything.
Why use it:
It puts search one keystroke away from every page without you having to find somewhere to put a search bar in your design.