How can I recover my accidentally deleted Mail App?

See the following from Delete built-in Apple apps from your iPhone, iPad, or Apple Watch - Apple Support

Restore a built-in app that you deleted

1. On your iPhone, iPad, or Apple Watch, go to the App Store.
2. Search for the app. Make sure that you use the exact name of the app.
3. Tap the Redownload button.
4. Wait for the app to restore, then open it from your Home Screen.

Also note that apps can be removed from the Home Screen without being deleted. If that is what happened, go to the App Library (swipe left past your last Home Screen). From there you can touch and hold an app and slide it to the Home Screen.

Click ▶︎ Mail app. ◀︎🙂‍↔️

Good luck! 👋🏼😉

Look in the App Library, the last page on the Home Screen. If you find it, drag it back to the Home Screen. Otherwise download it from the App Store.

I just need some deleted mails back