As somebody who has been trying to play harpsichord for many decades on and off, I immediately jumped to the chapter on tuning. My longstanding opinion on ET is that any key is simply a shift of x semitones above and below C.

Since publication when electronic aids were expensive, there's apps you can put on your phone for little or no money. Pitchlab Pro is excellent, but there may be patent issues in your jurisdiction. Also you now have to go through Amazon.

These days YouTube offers different interpretations of just about everything. It gives you something to aim for.