Creating a card to play a custom m3u over google mini group

Hi,

I’m new to Home Assistant and I’m absorving as much information as possible. Today I installed it on my Raspberry PI and I’m trying to create a card that plays a custom url m3u audio over my google cast group.

The problem is, I’m too new and I think I’m not doing things right since I’m missing basic things.

I’ve installed mini media player but I’m not sure how to add a custom card with the url so I can click play and cast this audio over my different speakers.

As a side question, I see most of the code that is shared on documentation has a particular indentation and dashes but when I copy paste that into the code editor for a card I need to manually fix the whole indentation so I think I’m missing things.

Thanks and sorry if this is a very basic question. I’ll keep reading documentation.