Apps disappear after I reinstall them on my iPhone 12

I was reinstalling an app and when it finished, it disappeared. So I tested this with another app uninstalled to see where it would go. As the app was installing, I held my screen in app menu where it would edit the menu so when it finished installing, the app instantly went to the top left of my screen. So when I exit out of the edit menu, it disappeared.

(I am using IPhone 12)

[Re-Titled by Moderator]

Original Title: When I reinstall an app, it disappears.