Classes and Functions

Question

I would like to learn more about Classes and Functions. Not just what they do, but rather how to use them and how to use them in the right way. The lessons here talk about them but are not going into depths about them.
Does someone know a site or other way to get myself comfortable with these (in my opinion) important part of programming?

Answer 1

http://www.cplusplus.com/doc/tutorial/classes/
http://www.cplusplus.com/doc/tutorial/functions/
https://www.tutorialspoint.com/cplusplus/cpp_classes_objects.htm
https://www.tutorialspoint.com/cplusplus/cpp_functions.htm

And other useful resources:
https://www.sololearn.com/discuss/459759/?ref=app

Answer 2

Have a look at these videos:
https://www.youtube.com/playlist?list=PLrhzvIcii6GNjpARdnO4ueTUAVR9eMBpc