This article explains how to request a song on Twitch using Nightbot or Moobot.
Twitch: How do I request a song?
Nightbot is a Twitch chatbot that can perform many functions, including taking song requests. To request a song on Twitch using Nightbot, you’ll need to find a channel that accepts song requests and verify that it uses Nightbot. Once you’ve done that, you can use a command to ask Nightbot to play a song from Soundcloud or YouTube.
Here's how to request a song from Nightbot on Twitch:
Find a song on Soundcloud or YouTube and copy the URL.