Writing a novel is a marathon. Writing that final scene is like finishing the long race.
I wrote the final scene to my WIP before I finished the first draft. They–whoever the writing experts are–say the writer needs to have the ending in mind before he starts writing. That may be true for writers who like to outline ahead, including me, but this advice may be difficult for other writers. However, whether the writer is a pantser or a plotter, here are some ways to end a novel: