ML from the Fundamentals
This series clearly explains the fundamental theories behind machine learning. I did not assume the reader has any experience with machine learning so anyone should be able to follow it.
Each does post assume you are familiar with the basics of linear algebra and calculus though. I could try to explain all math, but 3blue1brown would do a better job anyway so just watch his videos.
This series has a corresponding GitHub repository which you can find here.
Be sure to follow me on Twitter so you stay up to date with the series. I'm @rickwierenga.
Polynomial Regression from Scratch in Python
Logistic Regression from Scratch in Python
These are some resources I used to learn machine learning that you might like as well: