Actually it is possible to learn piano by yourself, and it much depends on how well do you wanna play. If you wanna be able to play, you can and it also depends on how much you practice.

If can, try to invest more than 1 hour and buy a adult piano lesson book and go through it slowly.

Of course, it is much easier if you have someone to guide you. Like when I learn piano, I had a very nice lady who is a piano teacher and my churchmate. Whenever, I'm at lost, like not knowing what key to press, she'd guide me, not to mention the counting and rhythm and etc.

When I started learning, i remember that I could knock each key correctly but I concentrate so hard on my fingers that I dont even know what I'm playing - no joke.

If you want this as a personal hobby, learning your own at a slower pace is indeed possible.