Here’s how to add chroma key (green screen) to your OBS shoot.

• Start OBS.
• Add a video source.
• Right click on video source and select ‘Filter’.
• Click + in the ‘Effects Filters’ section, and choose ‘Chroma Key’.
• Enter a name for the effects layer.
• Fine tune the settings.
• Add background layers.
• Make sure to send to the back.