You have to start somewhere, but if you're looking to learn the basics of formal art training, those are much more easily practiced in traditional drawing than in pixel art. Pixel art throws In a whole new set of challenges. I don't want to discourage you from pixelling, just know that learning the basics and practicing drawing regularly (especially from life) are essential to improving your technical skills.

The ghost itself is pretty boring. He seems to be the traditional sheet ghost, so maybe add some fabric folds in the white sheet, indicating where the fabric hangs off the forms underneath.you might also try making the ends of the arms tatteredformore visual interest. You might try googling 'sheet ghost' and finding a few references.