How do I add back an app deleted by accident?
How do I add a app back if I deleted it on accident
[Re-Titled by Moderator]
It depends upon the kind of app.
Delete [and restore] built-in Apple apps from the Home screen on your iOS 14 or iPadOS device or Apple Watch - https://support.apple.com/HT211833
Click on this link and read how to 'Redownload apps, music, movies, TV shows, and books' - https://support.apple.com/HT201272