I received a letter 12c from the IRS. Will I not receive any refund at all until I I send a 8962 and 1095-A?

No, you will not get your refund until this is resolved.  However, you can resolve this and send to IRS by following the steps below;

You will use your Form 1095-A to complete Form 8962 in TurboTax.

Follow these steps to input your Form 1095-A and Turbo Tax will fill out Form 8962.  Then you can download/print it to mail to the IRS with any other documentation they request.  

You can get back into the program by doing the following:

1. Sign in to TurboTax Online

1. Click My TurboTax
2. Click My Tax Timeline
3. Scroll down to "SOME THINGS YOU CAN DO"
4. Click Add a state under your 2017 tax return
5. Then, once inside your return, click My Account in the top right corner
6. Next, click Tools
7. Then, Topic Search
8. Type 1095-A in the search bar
9. When 1095-A is highlighted in the list, click Go
10. Follow the entry screens and double check your entries of 1095-A or enter it now

Is this way better than the other option given to click on “amend taxes”?