How to learn ethereum? Is there a guideline? What creates the value?

I'm a Bitcoiner since 2017 and want to understand why people buy ethereum fundamentally. What creates the value?

It's not the scarcity through the expansion of the market cap.

Is it the hope for usage in the future? If so, is there a working example for a useful project since the the release in 2015?

I'm sorry, but I never heard of one.

I try to compare it to Bitcoin and see no advantages. Can you help me?