A north window is just right for a Peace Lily. It needs protection from the rays of the sun falling directly on its leaves. But that means it also must be close to and in front of the north window to get enough light.
Water your Peace Lily thoroughly until a bit of water runs through the drain holes. Then watch it carefully and see how long it takes before it starts to just barely wilt. That will give you a pretty good idea how long it can go between thorough waterings. Occasional wilting will not cause permanent damage.
Fertilizer it monthly at half strength to encourage flowers. Also keep it potbound for improved flowering.
