Use without wifi or phone data

Do you mean you want to plan with talk and text only? AT&T does not have any plans without data. Even their cheapest Prepaid Plan includes 5 gigabytes of data.

Somehow I don't feel that answered your question. Would you like to try again and be more specific about what it is you're asking

Use it for what? Not having WiFi or cellular data means no internet access. You can use it as a camera or music player or play games or any other app that doesn’t need internet access. You can also use it for calls and texts presuming you have cellular service, just no data.

I know that you used to be able to get a call and text plans only for dumbphones, but now that all calls are over VoLTE, is there such a thing anymore? 

Even "dumbphones" today need LTE capability just to get calls.