Hey Bologna23,
Thank you for using Apple Support Communities!
I see from your post that you're looking to bring back the Mail app that has been removed on your iPhone X. I'd love to help.
I'd start here:
Remove built-in Apple apps from the Home screen on your iOS 10 device or Apple Watch - Apple Support
- On your iOS device, go to the App Store.
- Search for the app. Make sure that you use the exact name of the app. Find the correct name of built-in apps.
- Tap to restore the app.
- Wait for the app to restore, then open it from your Home screen.
If you have an Apple Watch, restoring an app to your iPhone also restores that app to your Apple Watch."
Cheers!