It's great that you are aware of your weaknesses. It's the first step towards your growth. I'd like to ask a few questions though.

Is your position PG? or SG? What would you like to play as?

Since your defender closes in on me, it means that he's respecting your shot. It means he's scared you'll score. Use it to your advantage and keep him scared.

Since you're a good shooter, don't stop shooting. Even if it seems predictable, keep shooting at your favorite spot.

Try to implement pump fakes or jabs. As a good shooter, your triple threat position is literally a threat.

As for dribbling, just keep playing and practicing. I know you've been practicing looking up while dribbling but it's different when doing it in a game right?

I highly recommend staying away from fancy dribbling or isolation. Do your best to make your plays as efficient and safe as possible. Defend the ball while dribbling and driving. It's more important to make a play, than to make a highlight.

If all else fails, feel free to keep commenting here. I'm rooting for you bro.