This article explains how to use Spotlight search on your iPhone or iPad running iOS 15 and iPadOS 15 and later.
How to Use Spotlight Feature on iOS15 iPhone iPad
Instead of searching through pages of apps, iPad's search feature lets you quickly find what you're looking for.
Spotlight Search searches your entire iOS device, including your music, contacts, and email. It also searches beyond your iPad or iPhone for results from the web and the App Store.
To open Spotlight Search on your iPad or iPhone, swipe down from the center of the screen to reveal the search field.