See the following instructions

conda create --name opencv python=3.7
conda activate opencv
pip install opencv-python
pip install pyinstaller

While in the conda environment you created earlier (named "opencv"),

Run pyinstaller --onefile hello.py

Then exe file will be located in .\dist directory

Run .\dist\hello.exe

(this command does not need to be run in a conda environment)

You should see a gray scale picture of footballer Lionel Messi. (color version is in ./messi5.jpg)

1. OpenCV Windows installation instructions
2. Create Executable from Python Script using Pyinstaller
3. Conda Cheatsheet
4. Getting Started with OpenCV images