1. A friendly guide to NLP: Bag-of-Words with Python example
https://www.analyticsvidhya.com/blog/2021/08/a-friendly-guide-to-nlp-bag-of-words-with-python-example/

2. Text Classification Using Naive Bayes: Theory & A Working Example
https://towardsdatascience.com/text-classification-using-naive-bayes-theory-a-working-example-2ef4b7eb7d5a