The Wedding (Episode 500): Naruto is approximately 20 or 21 years old.
The film ends with a montage of their wedding, not the ceremony itself. The actual wedding happens a few months after the film’s events. Here is what we know from the Naruto epilogue (Chapter 700) and the Naruto: The Seventh Hokage and the Scarlet Spring spin-off manga: when does naruto marry hinata