I took piano lessons from a young age and did up to gr. 5 piano exams with the Royal Conservatory of Music.
With no musical backround it can be extremely difficult to learn how to play specific pieces of music etc.
First you need to learn how to read and understand music - its like its own language.
I definitely think you could do it, but it might require lessons. If you just wanted to play a few simple tunes etc. I'm sure you could fool around with it and figure it out with some simple guides online but if you really wanted to play the music you would need to start from basics.
Its a really rewarding hobby/skill if you invest the time/energy. I hated it when I started at a young age. I hated practicing etc. but as I got older I really enjoyed it. Looking back I wish I didn't stop taking lessons when I did but I had to since I went to university etc.
I can't really tell you how difficult or long it would take you as that would all depend on how much effort you put into it but I would definitely reccomend trying and investigating it!
I would definitely look for a cheap electronic keyboard.. I know a ton of people who started taking lessons or trying to learn and quickly gave up or lost interest. I'm not saying this would be the case with you but rather real piano's can be very expensive! so I wouldn't risk wasting the money.
Check out these books (especially the Easy ones for a beginner like you):
http://www.alfred.co...=zelda&type=All
http://www.alfred.co...=mario&type=All
They are newly published. I have been debating ordering them recently!
Who knows? Maybe one day you'll end up like the guy in this video:
Absolutely beautiful music!