Android - How to reinstall an accidentally uninstalled app through ADB?

Technically the command adb shell pm unistall -k --user 0 does not uninstall an app from the device. Instead it just removes it from a user.

There are a couple of ways to get the removed app back to the user. One way is. Through an adb shell with the command:

adb shell cmd package install-existing <package_name>

Or an extreme way would be through a factory reset of the device.