Yes, you can send and receive text messages.
"With your phone you can send and receive SMS messages both via the fixed network and via VoIP. You must explicitly specify the line over which SMS messages are to be sent. You can receive SMS messages (SMS for short) via all connections of your phone except Gigaset.net. Your phone is delivered in such a way that you can immediately send SMS messages as soon as you have connected the phone to the fixed network. If you do not make any settings, the SMS are sent via the fixed network."
Operating instructions from page 63:
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