Ok, so I was looking that you can grow it in complete peat moss, is it true?

There'd be no problems provided you keep the orchid bark moist. They grow on trees with roots running over the trunk. The bark would allow air movement and at the same time keep the air around the Vanilla roots quite humid . What you'll mainly need to be successful is the right temperature.

Here is a pic. of a totally unrelated orchid that grows as I imagine Vanilla would grow in nature. Instead of the typical orchid habit these orchids looks more like vines.

Pseudovanilla foliata growin in a rain forest

Pretty much as Arthur said, but vines that attach themselves all the way. Going vertically they like to zig-zag. Here's one of mine on its way up a palm. There's another one on the palm in the top right hand corner.

But can i grow it in peat moss?

Probably not, cold and damp is usually a recipe for problems. If I tried to grow one I would bow to its requirements and train it up a tree-fern pole.

Too cold to grow it outside here in Zone 10b and it would need a heated glass-house which I have, but not heated to Climate Zone 12 temperatures.

Lots of good info. in the other current Vanilla thread.

A Climate zone next to your name would help posters give you good info.

So, just orchid mix?

Oh my gosh arthurum, I'm late with this, I'm in Las Vegas Nevada, zone 7a

7a inside for sure. It will not last a winter and there is no humidity. I think to grow Orchids where you live you will need to create a humid zone. Talk to the locals. They know best.

I'm growing it inside

It likes to climb. A trellis might work...

How big? 12 x 8?