Let's start from the beginning
It's you!

You are an ordinary beginner in GD and you are just learning to play. Good luck! Now I will try to help you with this!

You need to start with the basics of passing. Practice mode is a very important thing in the game. Before passing any level, you must pass it in practice! (Preferably even several times)

Congratulations, friend! Most likely you have started to pass the hard and harder difficulty levels
This is already a great achievement, but we will not stop there.
For more practice, I advise you to go through Map Packs and The Lost Gauntlets
You can also try to find simple demons on the Internet, for example, The Nightmare or THE LIGHTNING ROAD
There is very little left, my future pro player!!!

A few months later, there are already more than 50 demons on your account. You have passed a huge number of easy demons no less than a medium, even a few hard demons!
But now you realized that Insane demons are too difficult for you. You try to practice every day, but you still can't get through even 30%
You have strange thoughts and it looks like your skill has stopped at one value...

And now you understand what the answer to the main question is "How to beat your first extreme?" - Nothing.
You've decided to quit playing Geometry Dash and get on with your personal life. Self-development, progression, learning, relationships. You have found yourself and now you can spend your time only on those things that bring you pleasure