phone calls routed to two different locations by just logging into a phone

[GalwayGuy]

Newbie to this..... apologies for the basic, basic questions

Recently I was shown a setup were a guy could have his phone calls routed to two different locations by just logging into a phone at either location. He was using Blueface and some IP desktop phones. Basically I would like to be able to do the same.

I think I understand the basics and am wondering if you could give me directions as to what I should do??

1. I sign up with Blueface.
2. I 'port' one of my numbers (currently with UTVinternet) over to Blueface.
3. I get 2 IP phones and plug them into my routers.

Is it as simple as that?
How you use the phone to logon to blueface?
Is this just a function of the type of IP phone you get?
Any recommendations for phones that allow you do this?

Thanks for any advise you can give.