It's a good start, and I can definitely see a lot of potential in your drawing techniques. I would look into the following areas to improve.
Side note: I don't know if this character is your own design or a well known cartoon, but below are my general thoughts.
Hand anatomy - spend a bit of time drawing hands. Trace over some images, try to draw your hand etc. In this drawing the thumb and the palm on the right hand look a bit off.
Colours - The colours are either too similar or clashing - for example, the sleeves and the backpack are very similar. The lime green and pink don't complement each other, and the same can be said with the hair and the eyebrows.
Hair - This might be a part of the character's design, but the hair feels blocky. I'm not sure what the rings in the hair symbolise. The brown behind the hair also looks like a lump coming out of her head, rather than something coming out of her backpack. Maybe shading can fix that?
Shading - This may help the drawing. If it's not your style, then I completely get that. Maybe test it out and see what you think :)
Background - The tone of the background is too similar to the character's colours. Perhaps make it darker. Darker colours can really make a drawing pop!
I am super picky, but overall, this is a good drawing, and with regular practice, you'll definitely make some amazing art work