Hi Tye,
Now that you know where your python.exe file is running from spyder, install seaborn. Something like:
C:\Program Files\Spyder\Python -m pip install seaborn
This file path points to the exe file and explains to your machine which tool to use, then how to use the tool i.e which module (pip in this case) and the option (install).
Now try running your script from within Spyder.