Q.Planting bare root arborvitae
How do I store them after I receive them until I can plant them?

The packing material is generally paper that is moistened. Make sure this stays damp, but avoid drenching it.
Use some plastic to wrap the bare-root plants and store in a cool, dark place--basements, garage or sheds.
Keep them in temperatures between 40 and 60 degrees F.
This will keep your plants dormant and you can safely delay planting for about 1 week.
https://www.gardeningknowhow.com/ornamental/trees/arborvitae/growing-arborvitae-trees.htm