In the fanfiction, they could be involved in some sort of family activity at the Burrow. For example, helping Mrs. Weasley with the gardening or cooking. Harry could be learning some new magic tricks from Ginny's brothers, and Ginny is there to cheer him on and join in the fun.
Perhaps there's a bit of drama. Some old enemies or some sort of magical threat could be lurking around the Burrow. Harry and Ginny then have to work together to protect the Burrow and their family. They rely on their love and the skills they've learned over the years to face the danger head - on.
They might share some sweet and private moments. Maybe they have a cozy dinner together and talk about their future, like Ginny sharing her dreams of playing Quidditch professionally while Harry listens intently.