Using a headset on landline through the PC.

[#1]

As I have the Plusnet landline phone package with free calls, it makes sense to use the landline rather than using Voip, because the calls are of course all bundled into the package.  However, I would like to be able to use a headset and dial the landline from the PC.  I have Microsoft dialler, and dialling works well, but it does not connect the headset, only the usal BT handset.
On the other hand, I also use Microsoft fax when I have to, and that also works well.  So in view of the fax connection, surely there must also be a way in which I can route my landline through my PC, so that I can answer the phone using the PC and listen and talk using a simple headset ?
I do use the headset sometimes for VOIP and also for Skype, so I know it works through the internet connection.  But how do I use the headset to connect to the landline ?
I think the solution is probably obvious but probably dates back to the days of modems and dial-up internet and Windows 95 or even Windows 3.1 !!  So no doubt I am being stupid and forgetful, but what is the solution ?
Thanks

[#2]

Most data/internet modems have fax support, however few have voice support.  You will need to check that your modem has this facility.

[#3]

Aha.  So that's the reason and not my memory !  Thanks for that.  And I also imagine that a broadband modem does not work like the old dial-up modems either.  So I am probably wanting to do something that cannot be done.  Never mind but thanks for the response.

[#4]

you can double check if your modem supports voice by going to
Control Panel>Phone and Modem Options> Modems Tab> Properties>Diagnostics Tab> Query Modem
mine is a data/fax/voice/speakerphone modem but I can't recall what windows software can someone use for making calls