How to quickly refresh your memory and start learning Unity?

Question

C++ / C#

I haven’t coded at all for a year now, before that I was programming on Android in Java for about a year, I completed a couple of my projects.
Then he went headlong into his studies (there was an extreme course - term papers, tests, a diploma), there was no time at all.
Now that I have free time, I decided to learn Unity.
So, the question is as follows - How to quickly switch to C # from Java, which I forgot a little.
It's just that when I start reading books on C #, everything is so chewed up there that you already know 80 percent, and it becomes unbearably boring to read.
Maybe there is something in C # like "Python Bite"?
Or maybe give some advice.
Thank you very much in advance

Answer 1

Current: https://docs.microsoft.com/en-us/dotnet/csharp/pro...
Obsolete: https://msdn.microsoft.com/en-us/library/67ef8sbd(...