I am at a loss as to what you’re trying to accomplish. A good job following the instructions I posted. Your Mac was working fine, it certainly appeared.
You cannot “delete APFS” and there is no reason you should. I haven’t reviewed the YouTube video, but that seems seriously misguided. I have no idea what some random video is telling you to do. What problem made you dig up the video to begin with?
If you want a working Mac on Monterey, you might need to go back and follow my post again. That’s about all i can recommend.