The Contacts shortcut may have just been removed from your home screen, but I suspect it's still installed. Access the app drawer (often it's a circular icon containing a grid of dots at the bottom of your screen - on Samsung phones, if I remember correctly, it's on the far right end of the dock, and on most others, it's right in the middle. Or it could require a swipe up from the bottom if you're using a Pixel). Scroll around the app drawer until you find "Contacts," then press and hold the icon and drag it to the home screen of your choice.
On the other hand, if the Contacts app really HAS been deleted, or if for some strange reason your phone didn't ship with one, you can install this one from the Google Play Store: Contacts.