How important is knowledge of C# to work with the Unity API?

Question

Unity

I’m moving from Java, from a completely different field, I don’t want to read this good site https://metanit.com/sharp/tutorial/
for a long time, so I’m asking for tips: Which points from the site you need to know in order to fully work with the Unity API and editor, respectively. You can simply name from personal experience which sections of the language are the most important.

Thank you so much for helping me save time!