Hi, being a self made programmer I can understand this concern, I am totally from commerce background, I also had these issues when I started but things will get better with practice and theoretical knowledge. Machine Learning is a practical field but to reach at a level we first need to learn almost all the theoretical concepts.
So how to gain all the knowledge? Well the way I learned the same way I share at https://thecleverprogrammer.com/. So, I hope you will learn everything for free from here.