I believe verizon and other providers give 100 to 200 call blocks for free. I know the FCC has mandated they have these in place by 2020. I know the cellular companies have already placed these on customer lines both as free and upgraded pay service.
call blocking is available for home phones. Just google it.
The major phone providers are working on a solution.
If you want to read up on it, it is called STIR/SHAKEN.
The idea behind it is that the caller id will have to be authenticated.
In the meantime, you can subscribe (for free for landlines) to a service called nomorobo.
They will block a number of calls. It uses the simultaneous ring feature that is supported by FDV.
So you hear one ring and it stops.
It doesn't catch all of the calls. But I have been using it for over a year and it has greatly reduced that calls I get.