I haven't been able to fix this myself, but here's what I got from someone in the Discord for the game a while back, if it works for anyone, lmk:
#1 Thing to Try: Opening Game as Administrator
Steps:
Go to Steam --> Right Mouse Button on game icon --> Properties --> Installed Files (you can also verify the integrity of the game files while you are there, which is a smart idea) --> Browse --> Find "DeepSnowDelivery.exe" file --> Right Mouse Button --> Properties --> Compatibility --> "Run this program as an Administrator" --> Hit Apply
If that doesn't work, there's #2: In Windows, search "Graphics settings" --> Browse --> Paste path to the game file
If none of those work, you can go with my plan: Waiting till the game fully releases and hoping that it has better compatibiltiy (since at this point, I think my issue is that I just don't have a great graphics card)
Have fun!