All female staff at Auschwitz were SS auxiliaries (Helferinnen). Concentration camps were run by the SS. The women were named auxiliaries because only men could become SS members. All of them volunteered for the job, which paid relatively well and came with perks such as surreptious plundering of murdered victims' valuables.

Most of the total of about 200 women employed in the camp were guards in the Women's Camp at Auschwitz II-Birkenau, established in March 1942. But even those who were "just typists" were fully aware of what went on, as was everybody in and around the camp. The trains arriving, the thousands of people marched to several small buildings from which they never emerged, above all the smell... the smell of burning bodies was all around and inescapable.

Several of the more notorious female guards were tried and executed after the war. But as was the case with the men, most guards simply slid back into civilian life and obscurity.

/u/commiespaceinvader has previously answered the question What role did women play in the Holocaust (as perpetrators)?

EDIT: Yes, women who worked in Auschwitz-Birkenau knew the camp's purpose. I'm not sure what you mean by "know completely"? You don't have to hold the gun yourself to condemn someone to starvation, torture and death, be complicit in others' suffering. Maybe not everyone knew where all the camps were or about the work of the Einsatzgruppen on the Eastern Front, but they knew that Jews and other undesirables were being killed and cremated. Yes, they supported the genocide of Jews and Roma. Their hands weren't clean, but most of the clerical staff in the KL system weren't punished.