Letting your bunny live indoors is lots of fun as they can be very entertaining. They can, however, be destructive and you should prepare your house to protect both your bunny and your belongings. The best way to think about what trouble your bunny could get into if set free is to get down on the ground yourself and look around from a rabbit's viewpoint.
Most rabbits love to chew anything from carpet, electrical wiring and chair legs to paper, wall corners and plants. It is important that anything chewable is protected in some way or put out of reach wherever your rabbit is allowed to go. Many plants can be toxic to rabbits - if in doubt move it out of reach.
Some rabbits love to dig and carpet can become a lovely project for your bunny to work on. If your bunny takes a shine to a particular part of carpet you can cover it with something heavy such as a ceramic tile to stop access to it.
Set designated areas for your rabbit and stop it going to unprotected places by using panels from a dog pen or storage squares. This area can be increased as your rabbit learns what to play with and what is off limits.
If your bunny insists on chewing or digging you might want to use something to put them off it. Pet shops sell sprays to stop dogs and cats from being destructive but these don't always work with rabbits. Some people spray the chewable area with perfume or lemon oil which seems to have a positive affect if re-sprayed regularly. A spray water bottle is useful to target your bunny while behaving badly to teach them to stop.