This is a perfectly valid question. I have small hands, so I completely understand!  This won’t be a problem in beginning music and most intermediate music, but once you reach the point where you’re playing more difficult pieces, the chords and hand positions are going to become too demanding.  For me, I can stretch from my thumb to pinkie over eight notes (one octave) and sometimes, that just isn’t enough. As you get better on the piano and learn more about music theory, you’ll learn how to adjust chords to keep the music similar, but it’s perfectly fine if you have to adjust the chord to fit your hand size.  That won’t be a problem for a while, though!