Since no one has responded you could try the Greenhouse forum. But they'll need to know where you are located, what the greenhouse is made of and what you propose growing.

Here's a photo of the inside. The greenhouse will soon be airtight. We plan on using a 6 mil tinted poly plastic for the roof. Our gas will be on before winter. I don't want the tent to be too hot. Here in Alaska, the winter time can reach negative temperatures. I'm not sure if we'll need insulation or not. Appreciate you chiming in. Good day!

In Alaska? Where in Alaska? Nome? down by BC?

... you can put the plants into low tunnels inside the green house and gain more protection.

I would insulate the inside with some sort of clear air barrier, like bubblewrap or a layer of greenhouse plastic to minimize convective transfer.