Are bands just about internet access or does it affect cell calls too?

[chocolateyum]

Does the frequency say 3g 850 GSM refer only to the internet frequency or does that affect cell calls too?

I'm asking cause I'd like to buy a Chinese brand smartphone that doesn't have at&ts frequencies and use is as a cellphone without data. Internet connection would come from wifi.

Is that possible?

 

[Almeuit]

It could mess with calls if using VoLTE.