Context? You don't want to give away the whole plot. Yet you need to include enough to tell an interested person why to read the book. Who is the character? What happens? What is the genre? Best, sarkalark
Search out books in the genre you write in on Amazon. If you filter out the Kindle editions and just look at paperbacks, they allow you to view the back covers.
You will never write one that's good enough. Ever. And once you come to terms with that, you'll just write something to be done with it, which will turn out better than when you actually try to write something better. That's what worked for me anyway. Soon as you stop looking for that one specific Lego-brick, you step on it.