How to break down the goal of writing poetry?

1 Determine the genre you want to choose. For example, poetry and songs. Other points are different, but we can check them separately.

2. Make clear the theme of the poem. Such as lyric poetry, farewell poetry, ambition poetry, pastoral poetry and so on.

Make clear what you want to express before you start writing poetry, and turn it into a concrete picture.

Draw the picture you think and combine it with some emotional descriptions (all landscapes and words are emotional). We should gain perceptual knowledge by accumulating poems at ordinary times and learn from famous artists.

5. After completion, modify mediocrity and disappointment. Individual words will affect the whole work.

Your question is rather general, and the above is my simple explanation for you. If that's not what you mean, you can explain it again.