Welcome to the forum, Vattha!
The Suttanipāta is part of the Khuddakanikāya, the “minor collection” in the Pali canon.
Click on “Sutta”, then “Minor”, then select “PLI (which stands for ‘Pali’) Khuddakanikāya”—or you click on the respective green dots behind these words—and then you see a list of all the collections in the Khuddakanikāya, and you can easily find the Suttanipāta.
Silliness in its best sense is something I’ve come to appreciate a lot! 