A few things worth knowing

The blanks are fillable. Click any line and start typing. Save a copy when you’re done so your answers stay with the file.
On an iPad, use a stylus. Open it in Files, GoodNotes or Notability and write on it like paper. That’s the best way to handle the exercises that ask you to draw.
One page needs a pen. The Invitation / Challenge matrix asks you to plot a dot and a star, so that one wants a stylus or a printed copy.