Entered the wrong amount in the section that refers to 2018 State Tax refund worksheet: Item Q re: state/local taxes. I went back to fix it, but where is that page?

Did you already file your return?

If you didn't fie your return, Follow the steps below to correct the amount of 2018 state refund:

1. Log in to your account.
2. Go to Federal Taxes.
3. Go to Wages and Income.
4. Go to Other common Income.
5. Go to Refunds Received for State/Local Tax Returns.

If you already filed your return you need to amend it to make any changes.

Wait until your return has been fully processes and you received your refund ( if you are expecting a refund ), then amend your return. 

Here's how you amend your return:

1. Sign in to your account.
2. Scroll down to Your tax return & documents , select 2019 and then Amend (change) return. 
3. Select Amend using TurboTax Online.
4. Follow the instructions, your refund or tax due will change to 0. This is normal on amended returns.

Amended return can't be e-file, you need to print it and mail it in.