learn thing fundamental then derive the required concepts

Start clearing the basics first of the following topics of subjects which you are interested. 

Then you will be able to derive all the further essence of the concepts very easily.

Because you reached the baseline means you had laid a great foundation of your building knowledge. 

This can related to the abraham Lincon quote. 

I will be putting my 20 hours only for sharpening my axe then I will applied for the work. 

Reference : almanack of naval ravikant.