About the way of eating : The explanation of the first guy is correct (using three fingers).
But most of the time you don't use your bare fingers directly, you use bread to grab the food. You do something similar to this video [1].
For other dishes (Pastilla, couscous) you use your bare fingers. For couscous, the technique is a little bit difficult, you have to form a ball in your hand [2].
1: starts at 6:55 https://youtu.be/mH4wki8z5oI?t=410