How to learn in life

I didn’t know how to name this but I thought that with an effort on your part this title makes some sense. Well, let’s get to the secret right away.

There is no way to put more water in a bowl that is already full.

That sums it up. If you are willing to learn something, leave your previous knowledge, your prejudices, your opinions already formed at home and learn from scratch. Empty your canister. It may be that after learning you compare the new knowledge with what you already had and enjoy only a part of what you have recently learned, but you have learned.
It is not just because you are an instructor in a martial art that you cannot learn another from scratch without comparing to the one you have mastered.

The moment you think you know everything is the moment you limit yourself.

If when you enter a classroom or in a possibly constructive conversation, you already arrive with the walls raised, no knowledge will be able to enter, and at that moment you are not open for learning, you have already left the house closed.
Take a course for beginners, see materials for beginners. If a topic interests you, start at the beginning. Don’t let your ego limit your learning.
I had that in my mind throughout my adult life and in addition to never having done me any harm, it made me learn a lot of new things, I had many teachers and masters and made friends for life.
Be open to learn.