Without any internet from the provider, you would be unable to perform the above two tasks.
Now, there are options for users working with the previous versions of the technology.
The first step to begin with the method is to set up theGoogle Voice Account.

If you have done this step, then proceed further.
Fill your gadget with all the apps and accounts per the requirements.
Once done, open theHangouts app.

This app would be used to handle all of the tasks related to the method.
Each of the parameters shall also be handled through this app.
You would be able to set up this app easily.

Move ahead to this step and bring up the menu on the left side of the hangouts.
This could be done by pressing the three lines in the left-side corner.
If you are on Android, choose your account from the tweaks and then find the Google Voice section.
On iOS devices, the users must reach the controls Phone Number section.
Seek and initiate the Incoming Phone Calls option inside the above parameters page.
You also have to turn on the toggle for the Messages option on the same page.
Both options offer access to incoming messages or calls over the hangouts.
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