The Java Android course is really good.
Java is easy to follow and beginners can learn it easily and quickly.

Android is also easy to understand and I have watched many lectures, but this is the best one.

김재용

You will gain development experience through Java's basic grammar and object-oriented programming, and examples of creating real Android apps. 
This is the first step to Android and is the foundation, so I think you will understand everything if you study it step by step.