Complex sentence: The first is at the Ivolgins' apartment, where Nastasya Filippovna is visiting the household of her potential fiancé, Ganya, and meets Myshkin, who is renting a room from the Ivolgins, for the first time.
Split into simpler sentences: The first is at the Ivolgins' apartment, where Nastasya Filippovna is visiting the household of her potential fiancé, Ganya. Here she meets Myshkin, who is renting a room from the Ivolgins, for the first time.