Calling over WLAN using OpenWrt

Is there anyway to use openwrt as router or AP to make calls to connected phones(iOS and Android) within internal wireless network.
I have large home and want to connect and talk to family members.(No more shouting and screaming!!!)
I’m not interested in apps like Skype,etc
It should be using Wi-Fi or say as VoWIFi
Any possibility?

If you're talking about traditional phone calls, iPhones (and maybe Android) have a feature called wifi calling. This basically uses your wifi network and internet connection to send calls over IP through your carrier. I believe that many/most carriers support the technology, but it does depend on their support. Calls are still routed through their system... the difference is that the connection between your phone and their network happens via wifi rather than cellular towers. And these are still traditional phone calls.

Other than the traditional phone calls as noted above, how do you expect your phones to make and receive calls or messages of any kind? Even the phone functionality is technically an app on your device. You could also use FaceTime if you wanted, but also an app.

Thanks for your response.
In my iOS 15 I could not find Wi-Fi calling.
I understand your point, after all I would need to use app, but not those as mentioned Skype,etc as all such applications calling is blocked by ISP.
Any device is available to connect to router and use its soft phone app
I’m not sure how this works or technically possible what I’m looking for.
Just to add further, few years back there were applications for windows to make pc-to-pc calls.
Is there anything newer for smart phones.

You could install asterisk on your OpenWrt system, create your own PBX system and use SIP client applications, available for Android and iOS. In this case all the VoIP traffic will go through the router, but there are some inconveniences:

  1. It is not so trivial to make asterisk work.
  2. The SIP clients drain the phone battery faster.