If you want to retain a piece of information, a concept, or a mental model, ask why it is important.
The mind isn’t the greatest memorization tool, however, if a concept is important to one and he can ask and understand why it is the mind has a higher probability of retaining the information.
An example:
What is AI and why is it important? Why will it change the operations of X industry? What will happen to the productivity of X industry and why?
A constant questioning of information, and reasoning from first principles is how you can learn anything and most likely retain it.