Estimated taxes yet I am getting a refund from state

I just noticed my 2023 taxes included my first estimated taxes vouchers for federal. I owe federal 7k and got back 7k from my state. Is there a way to change my withholding or something so I don’t have to pay estimated taxes? 

 

Also, I accidentally e-filed my taxes and did not include the $10k 529 college savings. Is there a way to amend it? Never amended a tax return before. Do I amend only my state or federal as well? 

Thanks