A bunny only needs a very very small space to be able to escape: If the head fits, the rest of the body will be able to follow. It may seem unbelievable, but only until you’ve actually witnessed a little escape-artist actually go through an insanely small hole =)
It’s very nice of you to not have put her in a cage, as you’re saying, most cages are too small and don’t have enough space to play in. With young rabbits it may be good to have a cage to begin with though, and you can set up a playing-area outside of it made of NIC-cubes f ex. Look in the habitat-section of the forums for inspiration!
The most important thing to see to when you have a free roam bunny is to bunny proof the room she’s in. You’ll want to start by getting cable covers for all electric cords that you can’t put out of her reach (and bunnies have long reach). Bunnies are natural cheweres and young bunnies especially want to try and taste everything, and that is of course very hazardous when there’s electricity involved. Here are ideas for bunny-proofing: https://binkybunny.com/BUNNYINFO/tabid/53/CategoryID/8/PID/940/Default.aspx
Since you are new to bunnies you most likely will have a ton of questions in the near future, and we’ll be very happy to try and answer them as best we can!
‘