Can one really become good at Java just by going through the course here?

Question

Learn Java

Answer 1

No, not only from this course. BUT It's a great start. The course provides nearly all basics that you need. But to learn a language you must use it frequently like any other language too.
So my advice: "Start here and feel welcome. And then search for some programming challenges like r/dailyprogrammer on Reddit!"

Answer 2

not, it is a base, you must to learn more, practice and begin with small projects

Answer 3

yes you can