Missing app

The Safari app is not one of the apps that can be deleted but it can be removed from the home screen. Go to the App Library (swipe left past your last home screen). From there you can touch and hold an app and slide it left back to the home screen.

Also note the Search window at the top of the App Library.

If you were previously accessing the Safari app from the Dock, you can drag Safari's icon (located in the Applications folder) down to the Dock where an alias will be created for you to use.