How do I review my State tax from line-by-line? I need to understand why I owe $900+

Try previewing your actual return as it is a more accurate reflection of your return. 

You can get to your tax return(s) in TurboTax desktop as follows:

1. Switch to Forms Mode, and then  (see screenshots below for additional guidance)
2. Scroll through your forms in the left panel and 
3. Click on the form you want to preview (Example Form 1040)

You can get to your tax return(s) in TurboTax Online as follows: 

1. Go to "Tax Tools" in your left panel,
2. Select "Tools" and then 
3. Select "View Tax Summary" and 
4. Select "Preview Form 1040"

In TurboTax Desktop, it will look like this to switch to "Forms Mode":

Your left panel (list of forms) will look something like this:

In TurboTax Online Online it will look like this:

Click here for additional information on previewing your tax return.