I had 2 different jobs last year and now I’m having trouble adding my other W2 to my current form. One of them is already done, but i don’t know how to add the other one.

To add another W-2 in TurboTax, please follow these steps:

1. Click on Federal > Wages & Income
2. Under Wages and Salaries, click on the Update box.  You will see the screen, Here's your W-2 info. 
3. Click on the Add a W-2 link.  If you are filing jointly, you will see an Add a W-2 link for you and your spouse.  Make sure you click the right one.  Continue through the interview, entering the information on your additional W-2.

If you did not e-file yet, go to Federal>Wages and Income and add the W-2.  if you did e-file, that is why you have a problem.

If you e-filed with only one of your W-2's

You cannot change or add anything on the return that you just e-filed, nor can you stop it.  It is too late, just like when you put an envelope in a US mailbox on the corner.

If you left out a W-2, or a dependent, or a 1099 etc…DO NOT change your return while it is pending.  The changes will go nowhere.

Now you have to wait until the IRS either rejects or accepts your return.  If your return is rejected, you will be able to go into your account and make the necessary changes to your tax return and re-submit your return.

 If the IRS accepts your return, however, then you have to wait longer until it has been fully processed and you have received your refund.  THEN you can prepare an amended tax return and mail it in. You have to be able to work from that return exactly the way it was when it was e-filed originally.  You will need to use a form called a 1040X. You cannot e-file an amended return.  They have to be mailed, and it takes about 4 months for the IRS to process an amended return.

 Meanwhile, DO NOT go in and start changing anything on your return in the system, or you will make a mess for yourself.  Sit tight and wait until you see what the IRS does with the return you just e-filed