The term '\venv\Scripts\activate.ps1' is not recognized as the name of a cmdlet, function, script file, or operable program
Using the full path to the activate.ps1 script must work, otherwise something is not correctly setup in your venv environment.
C:\Users\Corey\Development_Cortuga\venv-test\venv\Scripts\activate.ps1
If the above still does not work, make sure py.exe and venv are available from your Powershell session:
py.exe -h
py.exe -m venv -h