Hello I looked in the tuts list but I couln't find any tutorial on normal idels of NPCs ... like if I want to place 3 or 4 npcs sowmehre in a camp doing this or that how do I do ?

Any?

in this tutorial you can learn basic use of idle marker
http://www.creationkit.com/Bethesda_Tutorial_Encounters


you can also drop some idle markers, if your NPC have a generic AI package, it will use them