As a grepper community member, I am recommanding you to learn any programming
language by making your hands dirty in it.
Dont't just watch videos to learn it as it is same as learn to swim by watching
youtube videos.
You can learn this language on a website that teaches you with giving some relevant
exercises on learning.
I am listing you some of the good websites that I know to learn a new programming
language in a right way,
1. https://www.w3schools.com/java/
2. https://www.learnjavaonline.org/
3. https://www.programiz.com/java-programming