How can I study the OOP perfectly?

Answer 1

try using it in code.

Answer 2

They are covered in the c++ course.
Keep going with the course and you will see:

https://www.sololearn.com/learn/CPlusPlus/1918/?ref=app

Answer 3

@Lebu Ayuga
This answer is completely unrelated to the question and also a 1 on 1 copy of jays answer to your own question.
Second outrageous copy I found on your account.

Answer 4

i like unity3d, you get a very good concept of OOP with c#