Voip help

I currently have a analog phone line that has unlimited long distance in the us. I want to remote it to where ever there is internet. For example i want to call long distance at work using a voip phone and i want my analog phone to ring at my desk a work too. What equipment do i need to set something like this up? I also don’t want to pay for any voip services. I want the voip phone to connect directly to my house anolog phone.

The end goal is to be able to carry a laptop(with wireless networking and an ethernet port) and have the phone work when ever i am in a working wireless area.