<Suggest me a reference for learning Kotlin , Java...

# stackoverflow

[user]

Suggest me a reference for learning Kotlin , Java
I really want to learn application programming and I have prepared tutorials in my own language, but all of them are not at the beginner level and have not fully explained.
I want a reference to teach programming to a beginner
Something that explains the code line by line and tells what it is used for
Please suggest me all the sites that have training
And that my second language is English, and it would be better if the lessons were free
And that I am taking kotlin, I want to master...