All roots died. What do I do?

[Skask]

I'm new to this forum. I'm also new to growing orchids. Well new in that I've killed two and really want to keep this one alive. I live in the western North Carolina mountains in the USA.

My orchids have suffered the same fate. They were given to me. I watered them and let them grow. But I never did anything else and the roots rotted and died. And then the plant died. Duh.

I asked a friend this time who grows orchids beautifully and she was the one who showed me that all the roots died.

How do I help the plant grow new roots? I put it in new sphagnum moss and a better pot to help it stay moist but not wet. After several weeks it is slowly dying of thirst and I don't see any new roots. I've just placed it in a warmer room and put the humidifier on to keep the humidity higher.

Should I be soaking it in water for a period of time each day/week?
Should I put some root growth powder/gel??? on it to encourage root growth?
I appreciate any suggestions. I don't want to give up yet.
S