how do I get to the live analysis board ?


Learn--> Analysis
Or, in your daily games, there is a chess board icon that will take you to your analysis board. Then, to make the move in your actual game, you do have to exit and submit the move on that board, of course.

https://support.chess.com/article/606-how-do-i-use-the-live-analysis-board
However, that will be going away soon when the old interface is retired. The functions of that are now in Learn > Classroom
https://www.chess.com/news/view/chesscom-releases-new-classroom-feature