this sounds awesome and i want one. i think its possible, you could even have alexa or some kind of speaking system built into it but it would be a lot of work. would be good for it to return to a docking station and charge itself.
someone has a facial recognition project here
https://www.hackster.io/gr1m/raspberry- ... ion-16e34e
it could be worth building a quadcopter
http://www.instructables.com/id/The-Pi-Quadcopter/
the auto pilot could be difficult, how would you do that? perhaps GPS or radar? you can get an auto pilot kit
http://www.robotshop.com/uk/navio2-auto ... i-2-3.html but id imagine you would need some kind of radar, movement detection, obstacle avoidance.
if its outside, maybe it would also need an Anemometer to measure the wind speed and know when not to take off?
im sure ive seen a project in the past where a guy had a raspberry auto pilot a drone with gps then for landing it on a docking station he had a second raspberry on the ground track and land the drone by sonar, but i cant find the project..
perhaps you can get lucky and find a project covering what you want, otherwise youll not be so much of a beginner once youve finished this one