A simple way to detect faces in a given picture in Python using OpenCV and Matplot libraries
You can find an article on this here: https://medium.com/@pradeepradyumna/face-detection-with-6-simple-steps-in-python-4e3958660dbe
Also, you can find my Colab notebook here: https://colab.research.google.com/drive/1cndOr-YmXH8ZBc6_QvwvuEoczBVGpO6O
References: The image I used here (from a popular American sitcom called Friends) is taken from https://www.nytimes.com/2020/02/21/arts/hbo-max-friends-reunion.html