It can take time for a bunny to settle into a new home and to feel comfortable with you. I have adopted rabbits that took months to want to be around me and to be petted. She is evidently feeling territorial and protective of her litter box and food bowl. That should change as she feels more comfortable in your home. Sit on the floor and let her come to you.
Was she just recently spayed? There can be a month or more of adjustment after their surgery, when they are dealing with the fluctuating hormone levels.
If your other rabbit has access to the gate that contains your new rabbit, make sure that they can’t reach each other through the gate. You may have to have a double barrier. You don’t want any noses or ears or other body parts to get nipped. Bunnies can hold a grudge and that wouldn’t be a good start to future bonding. Let her settle in for a few weeks before you even attempt bonding.