How do I turn on notifications for the icons on the home screen?

I just upgraded to a Nexus 5X with Android 7.1.1. I previously had an old Sony Xperia TL and when I received text messages or Facebook Messenger messages, a "1" (or whatever number of messages that I had received) would show on the main icon on the home screen. The Nexus does not do this. Is it possible to turn this feature on?