When you create content in Kaltura, it saves to your My Media site in Moodle. To make your content viewable to students, you need to go to the class, and add it as a Video Resource or Video Presentation.
Kaltura is a video creation tool that is integrated into Moodle. You can use it to create and upload video, import YouTube content, create video quizzes and media assignments. Kaltura will automatically caption your videos with about 85-90% accuracy. The tool also provides stats and analytics on who has viewed your video content.
Kaltura has two options for video recording: express capture and Kaltura capture. Express capture is just video and audio - you cannot share slides. Kaltura capture can be used for slide sharing, and also includes annotation tools.
If you have recorded Zoom sessions, or just prefer to use other video creation tools like Screencastomatic, you can upload the video file into Kaltura.
You can also import content from YouTube, but will lose access to some of the Kaltura features. One great feature is that it will remove ads from YouTube videos.
To use YouTube with Kaltura, use this document to get started.