I want to adjust my Maryland taxes due to other W-2 forms I just received and file my Washington State taxes in which the state doesn’t come up in the list. What do I do ?!

[xmasbaby0]

WA has no state income tax.  You do not file a WA return.

[MayaD]

If you didn't file you return, you can add the W-2 that you just received.

Report your W-2 on your federal return and the information will flow to your Maryland State return.

1. Log in to your account. 
2. Go to Federal Taxes.
3. Go to Wages and income.
4. Click Edit nest to Job (W-2).
5. Click Add a W-2.

 If you already filed your return, wait until the return has been accepted and you received your refund, then amend your return to add the W-2.

Here's how you can amend your return:

1. Log in to your account
2. Scroll down to Your tax return & documents.
3. Select 2019 and then  Amend (change) return.
4. Select Amend using TurboTax Online.Carefully follow the instructions. Don't worry if your refund changes to $0. This is normal on amended returns.

Regarding your second question,  Washington state does not have a personal or corporate income tax.