Yes. The handheld optical device you’ve seen is typically a director’s viewfinder. It’s essentially a small monocular/zoom finder with frame markings, used on film sets to preview framing and angle of view without bringing out the full camera.

For still photography, simple frame cards are still useful, but a director’s viewfinder can do the same job in a more flexible way. That said, still photographers often rely less on them because still cameras are relatively small and easy to raise to the eye.

If your goal is to learn composition without spending film, the most practical modern tool is a digital camera. It lets you experiment freely, review results immediately, and build your sense of framing much faster. You can then apply what you learn to your film cameras.

Also, studying strong photographs, paintings, and composition resources is a valuable complement to any preview tool.