The Fediverse has its own Twitch-style livestreaming platform called OwnCast:

➡️ @owncast

You can find out more from its official website at https://owncast.online

Because it's part of the Fediverse, you can follow OwnCast accounts from Mastodon etc, and when they go live you will see a post in your timeline to let you know.

For example, the RetroStrangeTV livestream can be viewed at:

➡️ https://live.retrostrange.com

...and it can be followed at:

➡️ @rstv

#Fediverse #OwnCast