Here is a list of free online courses for learning Java, C++ and Python. Here I have added courses I found helpful for beginners. I hope you will find helpful this article. Wish you best of luck!

Learn C++:

1. C++ Tutorial for Complete Beginners

https://www.udemy.com/free-learn-c-tutorial-beginners/

2. Beginning C++ Templates

https://www.udemy.com/course/beg-cpp-temp/

Learn Python:

1. Python Core and Advanced

https://www.udemy.com/ardit-sulce-python-for-beginners/

2. Learn Python 3.6 for Total Beginners

https://www.udemy.com/python-3-for-total-beginners/

3. Start Programming Today with Python!

https://www.udemy.com/free-python/

4. Try Django // Python Web Development

https://www.udemy.com/course/try-django-v1-11-python-web-development/

5. Django for WordPress Developers

https://www.udemy.com/django-for-wordpress-developers/

JAVA Programming:

1. Crash Course Into JavaFX: The Best Way to make GUI Apps

https://www.udemy.com/crash-course-into-javafx-the-best-way-to-make-gui-apps/

2.Java Tutorial for Complete Beginners

https://www.udemy.com/java-tutorial/

3. Practice Java by Building Projects

https://www.udemy.com/practice-java-by-building-projects/

4. Java Design Patterns and Architecture

https://www.udemy.com/course/java-design-patterns-tutorial/

5. Java Programming Basics

https://www.udemy.com/java-programming-basics/

6.Java Database Connection: JDBC and MySQL

https://www.udemy.com/how-to-connect-java-jdbc-to-mysql/

7. Java Multithreading

https://www.udemy.com/java-multithreading/

8. Developing Database Application using Spring MVC and MyBatis

https://www.udemy.com/course/developing-database-application-using-spring-mvc-and-mybatis/

9. Java Servlets and JSP — Build Java EE(JEE) app in 25 Steps

https://www.udemy.com/learn-java-servlets-and-jsp-web-application-in-25-steps/

10. Cucumber, Selenium & Java -Develop a Framework in 2.5 Hours!

https://www.udemy.com/course/cucumber-selenium-java-develop-a-framework-in-25-hours/

11. Data Structures in Java for Noobs (Lite Edition)

https://www.udemy.com/data-structures-in-java-for-noobs-lite-edition-algorithms-beginners/

12. Introduction to Docker for Java Developers

https://www.udemy.com/introduction-to-docker-for-java-developers/

Android Development:

1. Learn Android Application Development

https://www.udemy.com/learn-android-application-development-y/

2. Android Fundamentals: Ultimate Tutorial for App Development

https://www.udemy.com/ultimate-android-lollipop-app-development-course/

3. Android Development from Scratch to Create Cool Apps!

https://www.udemy.com/sisoft-android-basic-to-create-cool-apps/

4. How to publish an Android App on Google Play Store

https://www.udemy.com/how-to-publish-an-android-app-the-right-way/

5. Learn Android 4.0 Programming in Java

https://www.udemy.com/android-tutorial/