A beautiful sunset is the subject of both the photograph and the
poem. What theme is similar in both?

Natures Beauty

Explanation:

The theme of the beauty of nature is present in both the poem and the photograph. The sunset is one of the many beautiful things in nature, and both express the true beauty of it.

Of course, to give a more in-depth answer, a excerpt of the poem and the picture would be helpful.

Hope this helps!

i've read it so how can i ?

well basically since ima beginner people will answer any subject "right away"and if you get more points you could ask more questions or if you answer someone's question you get points