Windows 8.1 Dual boot tablet question.

Wasnt too sure which section to post this in but here goes.

I bought the Mrs a Teclast x98 3g Air Dual boot tablet. It has both Android 4.4 and windows 8.1.

I got it for her work and she uses a BT headset for the phone as the tablet takes a sim card e.t.c
Anyway all works fine under Android, but when running in Windows 8.1 it does not send or receive calls. I assume this is because the tablet is running Normal Window 8.1 and not Windows Phone 8.1.

My question is does anyone know of a way to get the extra bit of functionality into normal 8.1 to handle calls e.t.c
The tablet does see the sim card and it is all installed correctly, just seems like its missing a bit of software.

On a side note apart from this one issue the tablet is fantastic and very quick. Got it from aliexpress.com, arrived in under a week and was well worth the brass.

Thanks for any advice.