Plenty of pianists are completely self-taught. You can learn to play the piano by first familiarizing yourself with the instrument. Learn where middle C is, then learn the notes around it — these repeat themselves every octave or every 12 keys. Learn basic major and minor chords, then practice playing melodies with your right hand along with these chords. Reading music is fairly common with piano, but you can also learn without reading by training your ear. Try to play your favorite songs by sounding out the melodies and/or chords. As you go on, seek out theory such as scales and musical terminology and add these into your regular practice routine. Remember that practicing a little bit every day is far more effective than practicing for a long time every so often, as it builds better understanding and muscle memory. Taking an online course is a great way to learn at your own pace.