Learning rotation is important and there are lots of Taubman videos on YT that explain it in detail, usually with scales.

In a nutshell, there is the concept of single rotation and double rotation. When finger-to-finger movement is in one direction, like 1,2,3, you use double rotations. When going from 3 to 1, a single rotation. The movements are highly exaggerated for learning and demonstration.

I think it's easy to get hung up on "how can I play piano if I'm rotating my hand all over the place?" In my opinion, a large part of learning rotation and how to use it for slow practice on difficult passages is about freeing your arm and hand so they are not unintentionally opposing movement. Playing with tension or unintentional opposition, especially if you play hours a day, is one way to get RSI (tendonitis).

Here are some excellent YT resources for piano I have bookmarked. Several of these have videos that talk about forearm rotation:

  https://www.youtube.com/user/cedarvillemusic
  https://www.youtube.com/channel/UC3vYz1SAtcbRhsatydObGQw
  https://www.youtube.com/user/PianistMagazine (Graham Fitch)
  https://www.youtube.com/user/SteveMass1101
  https://www.youtube.com/channel/UCr0BMA5yu3AS0alkR7kYwEQ
  https://www.youtube.com/user/aw4piano
  https://www.youtube.com/channel/UCLsMRd097KLJMvkNzC4rYAA
  https://www.youtube.com/c/DanielBarenboim/videos
  https://www.youtube.com/channel/UC6tpkZhNpJiTnlUgoiUe9QQ