As of July 22nd, teens will have to be at least 16 years old to live stream on the platform, according to a support post. If a teen 13-15 years old wants to appear in a live stream, they’ll have to have to be “visibly accompanied” by an adult.
[Link: Avoid restrictions on YouTube live streaming - YouTube Help | https://support.google.com/youtube/answer/2853834 | support.google.com]