Q.sassafras sapling
I have found all kind of things of what to do with my saplings but none on how to plant them….I ordered them from a tree place and it came with no instructions. Do I bury the whole thing past the stem or leave some of the roots out? I just don’t know how deep and how far up the sapling I should go any help will be appreciated. Thank you.

The roots will need to be planted, no roots should remain above ground.
Here are some links with more information.
https://forestry.ohiodnr.gov/portals/forestry/pdfs/factsheets/treeplantingguide.pdf
https://www.gardeningknowhow.com/ornamental/trees/sassafras/what-is-a-sassafras-tree.htm