In learning mode, you can take your time to understand how the brain training exercises work.
The exercises in learning mode have no time limits, so you don't need to rush.
To start an exercise in learning mode, do not click on "Start training", but on "Show tutorial". There you find the button named "Learning mode". In this mode, there is no time limit, which should give you the opportunity to practise the exercise.
To exit the game, simply press the X-button.