How to Improve in Geometry Dash?

Hello! I’d like to ask a few questions about improving in Geometry Dash. I want to get better at completing increasingly difficult levels.

Are there levels that gradually help you improve, from simple to more complicated?

Also, are there levels where you can practice tricky effects that I’m not very good at, or where you need to use the dual player, which I find very difficult?

I still don’t know how to tackle demons. My current skill level ranges from Easy to Harder.

I understand that playing a lot helps, but I’m looking for specific levels or strategies to improve more efficiently.