Thank you feuer1 and odoaker2015!
It is indeed the "Preview" button that brings up those controls I am looking for: "Your Move," "Next Chapter, Play Again, Analyze" for good moves, and "Retry" for bad moves.
And from the tutorial video, I saw that the controls I want will appear without the Preview button if the Study is opened by someone other than the Creator. That is why I immediately see the control buttons when I open Yuhan's Studies, but have to press "Preview" to see those controls on My Studies.
It is indeed the "Preview" button that brings up those controls I am looking for: "Your Move," "Next Chapter, Play Again, Analyze" for good moves, and "Retry" for bad moves.
And from the tutorial video, I saw that the controls I want will appear without the Preview button if the Study is opened by someone other than the Creator. That is why I immediately see the control buttons when I open Yuhan's Studies, but have to press "Preview" to see those controls on My Studies.