On the Samsung Galaxy S8 you will find a protocol within the phone app that logs your last calls. So you can see very quickly with whom you have been talking to in the past on which date and for how long.
In the factory, however, you only see which calls you have made. If you are also interested in who you have used to write SMS messages with, then you must have this information displayed.
The following article explains how this works on the Samsung Galaxy S8:
1. Open the phone app on your S8 and switch to the "Last" tab within the app.
2. Tap the "Three-point symbol" in the top right-hand corner and then tap "Show messages".
The setting is applied and you can now also see who you have sent or received SMS messages to in the past.