In the UK, I think both parties to the call would need licences - and they’d need to be using callsigns - that’s assuming they’re using an amateur band. But it

In the UK, I think both parties to the call would need licences - and they’d need to be using callsigns - that’s assuming they’re using an amateur band. But it might be using https://en.wikipedia.org/wiki/PMR446 https://en.wikipedia.org/wiki/PMR446 which is open and licence exempt (though “base-stations” are prohibited).