Tasks for OOP, SOLID, and just sensible online PHP problems?

Question

PHP

Good afternoon.
I would like to pull up OOP, and everything described in the question.
For what, and, in fact, I am looking for an intelligent practical problem book. Ideally, there is a task, we solve it - and then examples of solutions, with explanations.
To start your own project and come up with tasks for yourself - the idea does not fit, I have already come up with everything that I could come up with. But I feel like I don't understand OOP.

Answer 1

The whole point of OOP is to keep data and functions in one object.
That allows you to encapsulate and share the development of objects to different programmers.
It is quite difficult to come up with an OOP problem for a small project that one person can handle.
When inventing a task, assume that there are several of you and you independently write different objects, agreeing in advance only on interfaces (public methods)

Answer 2

Try codewars . They offer tasks of different levels of complexity, you solve them there, they are checked by autotests and if everything is ok, they show how others solved them. You can also use your phone.

Answer 3

just get yourself a job...