I've made a page for the Death Note Fic Speechless but I can't put the tropes in a folder and I can't link the tropes to the pages about that trope. How do I do this? I tried going into edit on other pages and mimicking what they do but it didn't work.

Courtesy link.

If you're talking about the "Villainous BSOD/Villainous Breakdown" bit, you need to put nowik markup([==]) around the / to prevent it from linking to a single namespaced page(though putting two trope entries on one line is discouraged anyway). I've fixed that and taken the liberty of making a few stylistic corrections, indexing it and resetting the page type.