Pre-Climax: the antagonist shows their strength and plans. The reader starts to doubt the main character's success. The main character is usually caught off guard and doesn't see the antagonist's plan coming.
Climax- This is one single scene that encompasses the final moments of the overall conflict or the final battle. This is the moment that all tension and conflict has been building towards.
It's time to wrap it up nice and neat. Everything and every reason your character decided to move, leave or make a change has come to head. This is it, the decision is made and now, we need the characters to get settled in.
If your character has moved to Serenity, the house is set up, it's time for the character to start nesting, making Serenity their forever home.
It is also time for you to start uploading to the Inkitt site. https://www.inkitt.com/fanfic-oliviagaines-serenity
Closure: The skies have cleared and the storm is passed. Now it is time to take stock of what has changed. At this point, your character's goals and desires have either been reached or redefined.
All the tension from the climax is released and all loose ends are tied up. You need to fulfill the promises you made to the reader. And you can re-emphasize the theme if you want. This is also the time to set things up for the next book if you are writing a series. But the most important thing is to show how your character has changed, how they are different from when they started the journey.