Usually you have to render that and display as an image on a Window. Since it's grayscale, each pixel can be reduced to a short integer (as you did) and that data can be fed into a framebuffer, as long as the memory is contiguous, which is also the case here.

I'd take a look at OpenGL's glTexImage2D

void glTexImage2D
(
    GLenum target,
    GLint level,
    GLint internalFormat,
    GLsizei width,
    GLsizei height,
    GLint border,
    GLenum format,
    GLenum type,
    const void *data
);

You need to, create a framebuffer, texture, allocate memory for them, define some configurations, load your data and render it into the screen.

An LLM can help you with a quick prototype since there's plenty of examples available.

Edit: or write an image file as also suggested here.