Shallow Neural Network from scratch (deeplearning.ai assignment)

I recently started taking Deep Learning Specialization course on Coursera, and I'm enjoying it so much that I'm having even dreams of neural networks. I am currently on General Assembly London's Data Science Immersive course, of course we have a lot of projects, and all the lectures to catch up with, but we are on Christmas break, and I thought maybe I could make the best use of this break in addition to preparing my final project. Even though we have covered a broad spectrum of machine learning models and theories so far in our course, but we still didn't have a chance to deep dive into the topics of neural networks and deep learning. I'm sure that it will come later in the course, but to be honest, I couldn't wait. But at the same time, I don't want to just blindly fit and predict without understanding the underlying theory and concept of neural networks. So this was a perfect time for me to properly learn and try it myself.