Since iOS 13 users can control the removal of applications on the phone, whereby we have the right to set up to control the deletion, removal of applications on our device. Once you have enabled the delete deletion feature, even if you press and hold the application, the x button to delete will not appear anymore. Below is a detailed guide on how to prevent deleting apps on iPhone.
Instructions for setting up application deletion on iOS 13
Step 1:
At the main interface of the iPhone, go to Settings → Screen Time.
Step 2:
Screen Time interface , click Content & Privacy Restrictions.
Next enter Screen Time Passcode.
Step 3:
Click on iTunes & App Store Purchases → Deleting Apps.
Step 4:
Next, press the checkmark from Allow to Don't Allow.
Then immediately the setup will be executed, you will not be able to delete apps on iPhone.