I deleted my notes app. How can I retrieve the files?

I deleted my notes app.

Why?

Use App Library to search Notes app, see this Apple article:

Organize the Home Screen and App Library on your iPhone

Organize the Home Screen and App Library on your iPhone - Apple Support           

If you have find the app, tap & hold on the app, then drag to the Home screen & drop it.

See -> Delete and recover notes on iCloud.com

Delete and recover notes on iCloud.com