What version of Poser are you using?
With the faceroom, as from Poser 5 , it is doable to make a head texture from a foto.
Otherwise you have to make the texture yourself.
Mask obj's can be made from within Poser using the grouping tool. 
It 's all in the manual. ( and there are some turtorials )
Google is your friend. 

Poser 1, 2, 3, 4, 5, 7, P8 and PPro2010, P9 and PP2012, P10 and PP2014 Game Dev
"Do not drive faster then your angel can fly"!