User Manual Dash DCAF200GBAQ02 Tasti Crisp Electric Air Fryer + Oven Cooker

It is not made for dishes. It has a basket - you put food you would normally fry, like chicken tenders, mozzarella sticks, etc in the basket - do the time and temp - and the food comes out crispy and you slide it onto a plate, or a bowl. That’s it. Amazing, I love it. This is perfect size for 2 people.

You set the temperature and plug in the unit. Then when you set the time is will automatically start. The timer is apparently a physical timer in that should finish cooking then unplug the power, the timer will continue to countdown, but the unit, unplugged, does not heat.
To preserve the time indicators around the knob, I applied clear nail polish. Some people complained that over time the indicators tended to wear off, making it impossible to set the time specifically.

Yes unit turns off when timer ends. It also turns off when the basket is pulled out. If you want to turn power off when timer is not finished you could just unplug it and timer will finsh without power.