I've seen many similar images to this one on instagram and they've always resonated with me. After many attempts I figured out the key! Shoot at blue hour.
This one's far from perfect; I found the trifecta of under exposing, too high of iso, and too long of a shutter speed to achieve sharpness in the waves. The result is a slightly grainy and slightly unsharp image.
I think shooting just 15-30 minutes earlier would have given me more light to work with, but that's the joy of photography! Just continue progressing!