You could try reseating the internal display cable where it attaches to the logic board, but I think it looks like a failed LCD panel.
Probably to replace the top lid (display plus cables and the lid part of the case as a complete assembly) in the range of $300 parts plus labor. Minimum $250 if you do the repair yourself. Depends on where you look for a replacement display assembly.
Is it worth doing on a 5 year old laptop? Only you can answer that question... 😎