Livestreaming can be a simple as going live from your console to having a full stream setup with webcams.
As a baseline you'll need an account for a streaming website, a console that supports streaming or a computer, and an internet connection but you can enhance your stream quality with microphones, webcams and other elements.
Most modern generation consoles (PS4 & 5/Xbox one, S & X) have native support to live stream, and you can broadcast from your PC with software like OBS studio and Streamlabs.
Where:
You can setup a free account on live stream and video hosting sites such as Twitch, YouTube, Instagram, TikTok, and Facebook gaming.
Going live on PlayStation
Going live on Xbox
If there's no game running the stream starts when you launch it, and if there's already a game running the stream will start when you go back into the game.
To stop the stream, press the Xbox button and from the guide go to capture and share. Select 'Live streaming' and stop the stream. (You can also pause, and resume streams here).
Going live on PC (these instructions are for using OBS studio)
Use the + button in the scenes tab to create a new scene. This could be fundraising information, or just a 'BRB' scene for when you take a break.