Yes, but only with the LTE version, i.e. with a SIM card. The WLAN version does not support calls.

There are two versions of the Galaxy Tab S6. The one with WiFi and the LTE version. Calls to the fixed network are only possible with the LTE version. You can quickly find out which version you have. If your device has a slot for a SIM card, you can also use it to make phone calls. Calls with WhatsApp and the like are of course possible with both versions.