Hello - Exciting, yes!
After looking through the Quick-Manual (a bit meagre ...) https://consumer.huawei.com/en...

...the RJ11 or "LandLine" connection may or may not be present; if it is present, however, this does not mean that it can be configured and that it can also be used to make telephone calls or have a telephone connection set up. It would then be similar to our C-DSL or UPC router: we have connected our "analogue" telephone to it and use it to make phone calls via UPC - it is more or less a Voip bridge.

But it's not at all clear whether it's built into the Huawei, configurable if available or not - and above all how... quite typical "Chinese"... rep. just translated.

It's best to ask customer service:
https://helpcenter.digitec.ch/hc...

Hope that helps.