In all honesty, Atticus isn't yet perfect for poetry, mainly because its indents are designed with novel writing in mind. However, there are some options you might try.
Block Quote and Verse create padding around the top, bottom, and sides of your text.
To use these options, simply highlight your poem and click the corresponding icons from the main toolbar, located near the center of the screen.
If you find that there's too much space between lines for your liking, you can add soft line breaks instead of paragraph breaks between lines by pressing SHIFT ENTER.
For poetry with varying indents, consider using the hanging indent style. A hanging indent aligns the first line of a paragraph with the left margin, while subsequent lines are indented, providing a more traditional poetic line spacing.
If your poetry requires more than one level of indentation or intricate layout, your best option might be to create the poem in a design program like Canva or BookBrush, and then import it into Atticus as an image. This ensures that the layout will be maintained.