https://www.wairpodcast.com/episodes/category/First+Falling+Leafat the bottom of this page they play SINS. Im sure there are more out there.
There is also "powered by the apocalypse" ttrpg which is an apocalyptic world. I have played "Monster of the Week" which is based off the system. Lots of fun.
If you are just looking to get familiar with general dm advice. I love Arbiter of Worlds that Matt Colville recommends. He also runs a great series on DMing.
https://www.youtube.com/watch?v=e-YZvLUXcR8