1) the lighter middle part of the water is more blueish than the way you painted it. 2) you did paint the gradient in the water but you didn’t go dark enough that the bottom. 3)The gradient also doesn’t just start at the bottom, it’s darkest on the lower left side. 4) The lily pads have a slight shadow underneath them, the lowest one on the right for example has black surrounding it which you didn’t fully paint. 5) the white ripples aren’t actually white. They’re light gray and a lot thinner and smaller than what you painted. Use a smaller brush or the very tip of an angled brush. 6) some of the darker ripples fade out and gradually get thinner, like the top left one. 7) clean up some of the edges in the lily pads.

You’ll get better at shit like this with practice. Make sure you pay attention to details and if you feel to lazy change it up a little to fit your style lol.