If you have published an app on the App Store and wish to prevent users from searching for or downloading it, follow these steps:
1. Log in to your App Store Connect with your Apple Developer account.
2. Select the app listing for the app you want to remove.
3. Go to the “Pricing and Availability” section.
4. Scroll down and click on “Remove from Sale.”
See screenshot:
This will effectively make your app unavailable for users to download.
Meanwhile, if you also want to remove an app from your main view in Apps, log in to App Store Connect with your Apple Developer account, navigate to app information, and select Remove App.
See screenshot:
For more information, check this article from Apple: https://developer.apple.com/help/app-store-connect/create-an-app-record/remove-an-app
