OBSis a free program for video recording. You can create lectures by recording various screens through OBS such as PPT, programs, PIP and more by recording various screens.
Please follow the method below for recording
Initial Setup
Setting Up Screen Sources
Adding Screen Sources for Face Recording (Screen + PIP)
Checking Audio
Setting Recording Codec
Starting Recording and Saving
If the quality of recorded video is poor
You can record in better quality by increasing the bitrate in OBS. The recommended bitrate value is 2500~10000Kbps. After test recording, please check the quality and file size to adjust the bitrate value.