Not sure why Intuit still calls what they have in Link an "engagement letter" when it doesn't have the terms and conditions you should normally expect for your practice's protection and your clients'. If you must, copy the Intuit template and paste it (or, better still, use your own real engagement letter) on your letterhead.
I recall from the recent season update that Intuit would make their traditional organizer fillable. Until then, you can use the following (which are Lacerte organizers) from a ProConnect Tax article:
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